Poster Presentation Abstracts - osseo.org

Poster Presentation Abstracts

autogenous bone are additional time of surgery, donor site morbidity and a P176
limited number of available intraoral sites for harvesting bone. One method
of obtaining autogenous bone is to harvest it from an area adjacent to the Success Rate of Short Dental Implants supporting Single Crowns and
surgical site with hand held bone harvesting instrument during ridge Fixed Bridges.
augmentation with / without associated implant placement, and lateral wall
sinus augmentation procedures. The efficiency of the harvesting procedure may H.S. Malmstrom*, R. Cacciato, B. Gupta, A. Ghanem, G. Romanos, Y. Ren
depend on the type of the hand-held instruments used. Therefore, the purpose Rochester, NY.
of this report is to compare the efficacy of the different types of hand held bone
harvesting instruments and to discuss the indications and clinical uses of each Introduction: Short dental implants are an alternative option when vertical
device. ridge augmentation and/or sinus lift are not clinically feasible. The literature
in regard to success rate of short dental implants is limited, especially for those
P175 6mm in length with platform switch. The purpose of the present study was to
evaluate if there is a difference in success/survival rate of short dental implant
The Use of Light Cured Wax for Design of Copy Milled Bar. (6-8 mm in length)with platform switch, supporting single crowns and fixed
bridges compared to conventional dental implants (11mm in length). Methods:
J.X. Esquivel*, J.L. Hochstedler, M. Brindis, E. Kee New Orleans, LA. 25 subjects, who declined sinus lift and/or vertical ridge augmentation, were
recruited from the Rochester metropolitan area in upstate New York and
When implants are not placed in the ideal position for their future evaluated and treated at University of Rochester Eastman Institute for Oral
restoration this can create certain degree of complexity for the restorative Health. A total of 69 Astra Tech OsseoSpeed (Astra Tech, Molndal Sweden) dental
treatment. These complications can be either functional or esthetic. For this implants have been placed at this point. Of these 35 are short dental implants
reason custom–milled bars with integrated abutments can be designed for (all 4mm in diameter), 24 are 6 mm and 11 are 8 mm in length. 22 six mm and
further cementation of PFM Crowns. Conventional design of copy mill bars can 7 eight mm dental implants were placed in the posterior maxillae, and 9 six
be done with carving wax and pattern resin. For there to be enough space mm and 2 eight mm in the posterior mandible. Results: The lenght of time
for the restorations, a full contour wax up must be made prior to the design the implant supported restorations have been in function ranges from one
of these bars. This wax up must later be cut back and the abutments adequately month to two years (mean 372 days). Of the 24 six mm implants placed, one
designed. A 31 year–old male patient presented to LSU School Of Dentistry, was lost during the healing phase indicating a 97 % survival rate. In addition
department of postgraduate prosthodontics with a partially edentulous maxilla, one abutment screw fractured of the 6 mm implants resulting in a 92 % success
three implants were placed at sites 11, 12 and 13. To correct angulation rate. All implants of 8 mm length and conventional length (11mm), have
deficiencies, angled Low Profile abutments (Biomet 3i) were used. A copy milled remained without any bone loss or mechanical problems (100% success rate).
bar with incorporated abutments was required to correct the malposition of The 6 mm dental implant with mechanical problem was a single crown in the
implant of tooth at site 12. A copy milled bar was designed with the following area #3. The loss of the dental implant was likely caused by an insufficiently
steps. A full contour wax up of the edentulous area was made with carving wax mineralized bone graft that was placed in the socket when the tooth was
(Remfert). It was decided not to cut back, but to duplicate the waxed up model. extracted. The abutment screw fracture occurred in the maxillary molar region
An omni vacum form was made on the duplicate model. The waxing sleeves (#3) with a very tall crown with a large occlusal table which may have submitted
were placed on the working model, with the laboratory analogs. The omni the abutment screw and implant to overly high occlusal forces. Conclusion:
vacuum form was placed on top of the working model. Metacom systems Although there was a loss of one implant and one mechanical failure with the
hybrid light cured wax (Primotec) was injected into the omni vacuum form 6mm implants, the success rate at this early stage in the study is very promising.
placed on the working model, capturing the implant waxing sleeves. The wax More long term follow up and more subjects are needed to be enrolled to draw
was light cured in a light–curing unit (Primotec) for 5 minutes. The structure any further conclusion.
was then ideally prepared for PFM crowns with a high–speed handpiece and
diamond burs. All undercuts or concavities in the design were covered with P177
hybrid light–cure wax (Primotec) and sent to scan to Biomet 3i, for the
fabrication of the Copy milled bar. The use of the hybrid light–cured wax made Osteopromotive Property of Allogenic Demineralized Dentin Matrix.
the design of the bar easier as it shortened the steps to have an ideal design.
This type of wax provides more stability to heat distortion that conventional N. Bakhshalian*, S. Hooshmand, S.C. Campbell, B. Arjmandi Los Angeles, CA.
wax can suffer during shipping, and it is easier to use than pattern resin. Even
though computer softwares can design most milled bars, in some cases it is The objective of this study was to evaluate the osteopromotive property of
necessary for the clinician to predict where the position of the crowns will be allogenic demineralized dentin matrix (DDM). There are different kinds of grafts
prior to fabrication of the milled bar. and biomaterials being used for bone regeneration that are neither cost
effective nor free of complications. Therefore, it would be ideal to utilize teeth
that are extracted from other individuals (due to orthodontic treatments or
wisdom teeth extractions, which are routinely discarded) to make an
appropriate bone regenerative material, allogenic DDM. We hypothesized that
allogenic DDM has bone regenerative properties. To test this hypothesis 30 New
Zealand White rabbits were used. The rabbits were divided into four groups
and sacrificed after 15, 30, 60, and 90 days. The thickness of bone specimens
were measured before utilizing for micro-CT. Blood samples were collected from
all rabbits at each time point. Average bone thickness was increased by 54%
in experimental group and was significantly higher at all time points. Moreover,
microstructural properties showed superior bone quality in experimental group.
White blood cell count was numerically higher in control rabbits compared
to experimental rabbits ruling out any inflammation or infection due to
allogenic DDM. The results of the present study indicate that allogenic DDM
significantly improves both bone quantity and quality through its
osteoinductive and osteoconductive properties.

P178

An Open, Prospective, Controlled Study in the Maxilla to Evaluate Clinical
Outcome of AstraTech Implants, MicroThread™ OsseoSpeed™, in Single
Tooth Replacement in Smoking Patients using an Immediate Loading
Protocol in Healed Ridges and Flapless Technique: 1 Year Follow-up.

A. Scoccia*, M. Rocci, A. Rocci Chieti, Italy.

Immediate implant placement and loading after tooth extraction present
considerable advantages over treatment modalities. But smokers patients are
usually excluded from clinical trials because smoking has been found to have

114

Poster Presentation Abstracts

deleterious effects for oral health. Aim of the present study is to evaluate the answers the investigated question. Review of literature begins without
clinical outcomes of Fixture Osseospeed when used in post-extraction sockets restriction of articles to try to establish a consensus. CONCLUSION: There is
in smokers patients. This will give important clinical informations about needed RCTs who evaluate the effect of the KM about implants, since in
Osseospeed when placed in smokers patients and indicate weather flouride conditions of good oral hygiene there is not evidence that absence of KM
surface may help osseointegration process in this patients when a puts in danger the perimplant health, nevertheless, presence of KM benefits
postextraction procedure with immediate loading of single elements is used. the aesthetic and functional results of the implant-supported prostheses.
A total of 34 patients were selected. After selected tooth extraction, a total of
45 implants were placed according to guidelines. No regenerative procedure P181
was performed. The temporary crowns were all completed and installed within
24h. Final restorations were delivered after 6 to 12 months. Oral examination Implant Placement in Anterior Post-extraction Sites: Clinical Case
and radiographs are planned at 6, 12 and 24 months follow-up visits. Partial 1 Presentation.
year results show a cumulative implant survival rate of 97.8%. In fact only one
fixture has failed, for lack of osseointegration and within the first month from A.M. Malagon-Wintergerst*, G. Marin Mexico City, Mexico.
its insertion. All other implants have display excellent primary and secondary
stability and an excellent success of the prosthesis installed. There have been Bone healing of extraction sites proceeds with external resorption of the
no signs of inflammation or major changes of soft periimplant tissue. Intraoral original socket walls and a varying degree of bone fill within the socket. The
radiographs showed an average perimplant bone resorption in the first 12 survival rate of immediately placed implants (Type1) was reported in numerous
months of 0.36 mm (SD = 0.75). Therefore, we can assert that the procedure studies to be similar to that of implants placed into healed ridges (Type4). Type1
of single tooth replacement in smoking patients using an immediate loading placement refers to the placement of an implant on the day of tooth extraction
protocol and flapless technique had wide success, with excellent clinical results (Hammerle, 2004). Hammerle in 2004 mentioned the advantages of this
and minimal periimplant bone resorption, confirming the high performance of treatment; reduced treatment time, less numer of surgical procedures, and
this flouride implant surface even in conditions of single element immediate optimum amount of bone for implant placement. Disadvantages included
loading in smoking patients. We are waiting to collect the final results of the dificulty placing the implant due to site morphology. Clinical case: 46 year old
second year follow-up to make a definitive estimation of the parameters female patient, alergic to penicilin, who presented a poor crown to root ratio
analyzed. and a root fracture in the apical third of one central incisor. After phase 1
treatment, atraumatic extraction of 12, 11, 21, 22, 32, 31, 41 and 42 were made
P179 with periotomes, with minimal trauma to hard and soft tissues. With a surgical
stent, four Straumann BoneLevel Implants were placed, flapless technique in
Guided Surgery in Implantology. 12, 22, 32 and 41. Implants achieved primary stability and were placed in the
ideal restorative position. The rest of the alveoli were preserved with autologous
J. Mariano*, J. Gervasio, J. Junior Brasilia, Brazil. bone and xenograft. Fixed provisionals without function were placed. Results:
This technique allowed the maintenance of the integrity of soft and hard tissues.
Description of guided surgery in implantology and its characteristics. The Implants were restored with great esthetic success 4 months after placement.
paper addresses the aspects which comprise and define one of the most current Regular maintenance appointments will be scheduled to ensure the long term
techniques and discussed in contemporary implantology. The approach is on success. Discussion: Several studies assesing ridge preservation techniques
the whole technological process to implantology that step by step led to the for maintaining the dimensions of the bone after tooth extraction showed that
development of the technique of guided surgery. On the work isn`t considers despite the use of barrier membranes or bone grafts with low substitution rates,
the chronological aspect of the subject, the objectives is to acquaint the reader horizontal resorption of 13-25% still occurred (Lekovic et al,1997). Conclusions:
about the definition of guided surgery and the concepts of technological A number of prospective and retrospective studies have been published
attributes that comprise : computerized tomography, planning software, rapid confirming the high survival rates of over 95% of immediate (Type 1) implants
prototyping, stereolithography, surgical guides and features one of the for observation periods from 1-5 years (Wagenberg and Froum,2006).
techniques used in guided surgery. Shows by reviewing the literature, the
changes caused in implantology, the jump in quality and expansion of
procedures in diagnostic capability with the absorption of new technologies
to dentistry.

P180 P182

Importance of Keratinized Mucosa around Dental Implants: A Review. Immediate Load in Total Edentulous Jaw: Change in Capture Technique
of the Metal Cylinders for Immediate Non-metallic Provisional Prosthesis.
O.M. Ramón*, M. Restrepo, N. Otalvaro Medellín, Colombia. A.C. Montenegro*, G. Pimentel Neto, R.C. Carneiro, F.F. Costa,
S.P. Montenegro, K. Temponi rio de Janeiro, Brazil.
BACKGROUND: The influence of the dimension of the keratinized gingiva
in natural teeth on the health of hard and soft tissues is historically controversial; The immediate load in total edentulous jaw is a procedure well documented
the interest grew recently on the value of the presence/ dimension of the in dental literature, with high rates of success since you establish a proper
keratinized mucosa (KM) in the implantologic prognosis and success. Biological surgical Protocol, reaching primary stability, reduced surgical trauma, correct
and clinical rationalization for the presence of KM around implants is based distribution of the implants that favours Biomechanics and correct selection of
on statement that tissues are different in infection resistance due its structural clinical case. The provisional prosthetic rehabilitation in many cases keeps the
characteristics (reduction of capillaries and collagenous fibers, parallel implants united through rigid metallic bars, preferably with passive settlement,
disposition of fibers, absence of cement and periodontal ligament). Clinically
the KM presents a dissipation effect on muscle traction forces, better resistance 115
to mastication trauma and brushing; and favor less accumulation of biofilm
versus alveolar mucosa. In contraposition, the evidence does not support a
direct relation between the presence of KM and the inflammatory condition of
the tissues, nor his influence in the survival of implants in patients with suitable
hygiene. OBJECTIVE: To obtain evidence that clarifies the controversy on the
importance of KM around implants and its association with the Health Status
of the supporting tissues. The problem to resolve places in: which is the effect
of the presence or absence of the KM around the implants? SEARCH STRATEGY:
148 articles were checked in English published between january/2001 and
march/2011 in the databases The Cochrane Library(2), Medline/PubMed(22)
and ScienceDirect/Elsevier(126) by means of electronic search with the terms:
Width keratinized gingiva; Width keratinized tissue; Dental implant, limited to
human and clinical controlled randomized studies (RCTs). Only they are included
patients’ RCTs with implants with or without KM with evaluation of clinical
parameters (width KM/GI/PI/PD/recession/bone loss) for minimum 6 months.
RESULTS: Only 4 of 148 articles fulfill criteria of incorporation; nevertheless none

Poster Presentation Abstracts

avoiding micro-movements of the implants inside the bone, which may induce anesthesia were performed the resection of lesion and teeth extraction followed
the formation of a capsule fibrous. This clinical case was developed on the by autogenous bone reconstruction. Onlay intraoral bone blocks from
surgical concept of “all on four” immediate load, however the provisional retromolar region were fixed with titanium micro screws in conjunction with
prosthesis has been carried out only with acrylic resin without any metallic rich platelet plasma (RPP). The results of histopathologic study were multicystic
reinforcement. The goal of this poster is to describe a change in capture fo¬llicular ameloblastoma. A control postoperative CT scan was performed
technique of the metal cylinders for better and faster provisional prosthesis six mon¬ths after surgery, confirming consolidation of the graft. Reentry was
outcome. performed at 6 months after first surgery to retrieval of titanium micro screws
and placement of osseointegrated implants. The patient was followed up in a
P183 period of 5 years after prosthetic rehabilitation and there is no evidence of
recurrence. Conclusion: The treatment performed in this case confirmed that
Implant Placement for Epithetic Reconstruction using CBT-based Surgical a conservative approach is a good option for treatment of follicular
Guides. ameloblastoma.

M. Scheer*, J. Neugebauer, L. Ritter, T. Dreiseidler, J.E. Zoeller Cologne, P185
Germany.
Muco-implant Supported Overdenture using an Immediate Loading
Placement of dental implants for epithetic reconstruction after ablative Protocol: A Clinical Case.
tumor surgery in the orbital region is hamperd by the limited bone volume.
Additionally injury of the dura mater and brain or sinus frontalis should be M.P. Natividad*, O. Diaz de Ita Mexico city, Mexico.
avoided. In order to obtain an optimal and safe implant position preoperatively
virtual planning and transfer to an individual surgical drilling guide is Introduction: Immediate loading is defined as loading a restoration placed
mandatory. The aim of the presented pilot treatment was to evaluate the into occlusion with the opposing dentition within 48 hours of implant
feasibility of implant placement after virtual CBCT-based planning procedure placement. (1). Balanced occlusion is achieved when the immediately positioned
and fabrication of a surgical guide. A 56 year old male was treated by exenteratio prosthesis opposes a maxillary denture. (2)Ledermann (1979) used immediately
of the right orbit because of recurrent basalcellcarcinoma (fig 1a). loaded TPS screws to stabilize overdentures in the mandible. This technique
Reconstruction of the cheek was performed using a free latissimus dorsi flap. reports a survival rate of 91.2%. (3) Successful premature loading protocols
For retention of the epithesis, carrying the eye three implants were planned require a careful and strict patient selection aimed at achieving the best primary
in the latero-cranial right orbita using CBT device (Galileos, Sirona, Bensheim, stability. (3) Clinical case: 64 year old male patient, who was robbed and as a
germany) and implant software (SICAT, Bonn Germany). The bite plate with the result his conventional overdentures got fractured. In order to return his
radioopaque markers was fixed on a provisional pattern resin guide and three masticatory, esthetic and phonetic functions, and taking into account bone
osteosynthesis screws (fig 1b). The final drilling guide was produced after the quantity and quality, systemic health and occlusal factors, an immediate muco-
referential radioopaque markers were identified by inserting SICAT titanium implant overdenture following immediate implant placement protocol was
sleeves with an internal diameter of 2mm. The insertion of the implants was proposed. Four SLActive Straumann implants were placed (4.1mmθ, 10 and
done in general anaesthesia. The final surgical guide was mounted on the three 12 mm of length) in sites 12, 13, 22 and 33. 0.5grs of PUROSS and a non-
screws and the 2 mm pilot drill (XIVE,Friadent, Mannheim, Germany) was reabsorbable membrane in site 33 were used. Utilizing balanced occlusion, a
utilized. Three XIVE S Plus implants were inserted. After 3 month of subdermal muco-implant supported overdenture was then placed in the mandible and in
healing magnet attachements were inserted and the epithesis was finalized. the maxilla a conventional overdenture. This treatment plan required specific
Although the marker bearing bite plate as well as SICAT software was developed characteristics to succeed: Host related factors: Bone quality and quantity; the
for dental implants, the work flow could be adapted for craniofacial implant implants were placed in class 2 bone according to the classification of Lekholm
placement either. and Zarb, this compact dense bone ensures initial stability and will be able to
sustain immediate forces better.(5) Wound healing; patients systemic health
is adequate, with no healing risks. Implant-related factors; the surface coating
used was SLActive; this rough surface provides an increase in bone-implant
contact. (5) Implant length; 10 and 12 mm of length were used taking into
account the minimum required to ensure a high success rate. (5) Occlusion
related factors; bruxism was not present. The muco-implant supported
overdenture has been in function for the last six months. The loading protocol
used reduced the treatment time, patient discomfort and regular maintenance
will be needed to ensure the long term success of immediately loaded implants.

P184 P186

Treatment of Mandibular Ameloblastoma using Intra-oral Graft and Evaluation of Alloplast Putty and Xenograft Particulate as Bone Graft
Implants: A Case Report. Substitutes in a Sheep Lumbar Spine Model.

L.B. Moraes*, E.J. de Moraes, N.B. Moraes Rio de Janeiro, Brazil. A. Gonshor*, J. Zhong, D. Gaisser Athens, Greece.

Introduction: The mandibular ameloblastoma is a benign odontogenic Introduction: The objective of this study was to evaluate the local response
tumor that develops from the remaining components of the enamel organ. It to a synthetic graft material, Calcium Phosphosilicate putty (NovaBone Putty,
is a slow growing, locally aggressive tumor capable of causing facial deformity. NovaBone Products, Alachua, FL), as compared to anorganic xenograft (Bio-
It has a high recurrence rate due to its capacity to infiltrate trabecular bone. Oss, Osteohealth, Shirley, NY), for the repair and regeneration of osseous defects
The literature presents options to treatment of ameloblastoma with in a sheep lumbar spine model. Methods: 12 male sheep, with an average age
conservative or radical approaches. Aim: The aim is to present a case report of 2.5 yrs, were selected for the study. Using a left lateral retroperitoneal
of ameloblastoma that was performed a mandibular resection associated to approach, a skin incision was made adjacent to the lumbar spine. The psoas
autogenous intraoral graft followed by osseointegrated implants rehabilitation.
Case Report: A 24 years old female patient of authors clinic presented in a
panoramic radiograph and a CT scan similar images to multicystic
ameloblastoma, involving teeth with buccal cortical swelling. Under general

116

Poster Presentation Abstracts

muscle was retracted to expose the 3rd, 4th, and 5th lumbar vertebral bodies.
Beginning with L3, an intra-body defect 8 mm in diameter and 15 mm deep
was created in the vertebral body using sequentially larger surgical drill bits.
Once created, the defect was irrigated with normal saline and filled with the
appropriate graft material. The graft materials were prepared for placement
as listed in their Directions for Use. Caution was used to avoid excessive
compression during insertion of the materials into defects. Following filling
of the lateral defects, cortical bone disks, prepared during the initial stages of
the defect creation, were used to cover over the surgical defects and retain the
graft materials. Animals were euthanized at 6 and 12 weeks and the spines were
dissected for histological analysis. Results: A statistical comparison of the
histology was made at 6 and 12 weeks, using the One-way ANOVA statistical
method, with p < 0.05. Statistical differences were analyzed using a Bonferroni
pairwise comparison. Significantly smaller particle sizes were noticed in the
alloplast group compared to the xenograft group at both 6 and 12 weeks. A
statistically significant higher percentage of new bone, as well as lower
percentage of residual graft material, was seen with the alloplast putty as
compared with xenograft, at both time points.

Bone Regeneration in CPS Putty vs. Xenograft at 6 and 12 weeks

P187 P188

An Evaluation of Strengths of Various Dental Implants from a A Novel Method for Assessing Implant-abutment Connection Seal
Standardized Fatigue Testing. Robustness.

P. Gubbi*, R. Towse, B. Davis Palm Beach Gardens, FL. Z. Suttin*, R. Towse, J. Cruz Palm Beach Gardens, FL.

OBJECTIVE: This study evaluates the fatigue strengths of implants made OBJECTIVE: The aim of this study is to develop a method for characterizing
from various manufacturers (BIOMET 3i, Nobel Biocare, and Straumann). The the implant-abutment seal capability of dental implant systems subjected to
study specifically compares the endurance limits (highest fatigue loads without dynamic loading conditions. MATERIALS AND METHODS: The apex of a test
failure) determined from testing of these implants using worst-case scenario implant was modified to have a barb fitting, and a thru hole was machined to
with custom 30-degree angled abutments using the guidelines as specified reach the internal aspect. The implant was fixated in a block, exposing 3 mm
in ISO14801. MATERIALS AND METHODS: Bone Level implants (Straumann, of the coronal portion while allowing access to the apical barb. Tubing was
3.3mm D x 13.0mm L), Osseotite 2 (BIOMET 3i, 3.25mm D x 13.0mm L), and connected to the implant barb, and an abutment and screw were loosely
Replace implants (Nobel Biocare, 3.5mm D x 13.0mm L), closest possible assembled to the implant. Red dye was bled through the system using a
comparative size implants, were used for strength evaluation in the study. All peristaltic pump. The recommended screw torque was then applied, and the
implants are made from commercially pure Titanium metal per information system was thoroughly rinsed. The block was mounted at 20 degrees off-axis
available from manufacturers. Custom 30-degree angled abutments and in a clear tank filled with water. The pump was turned on and a high resolution
matching screws, both made from Ti-6Al-4V alloy were used in the testing. video camera at 50x magnification was focused on the implant-abutment
Mechanical testing was conducted to evaluate the endurance limits of the 3 junction (IAJ) to qualify the seal (i.e., lack of red dye leaking from the 7 PSI
implant systems per ISO14801 methodology with loading being done at 40- pressurized internal volume). If no breach was detected, the abutment was
degree to the implant axis (10-degree under corrected). RESULTS: The endurance cyclically loaded at 100N for 100k cycles with the pump off to represent system
limits from the fatigue testing for the 3 implant systems are 164N, 229N, and wear. After the wear cycle, the seal was qualified by turning the pump on and
259N, respectively, for Straumann Bone Level, BIOMET 3i, and Nobel Replace. visually monitoring the IAJ while loading at 2 Hz, 100N, for 1k cycles. If the
Figure 1 shows the graphical representation of the test results. It can be seen sample successfully completed the qualification, the entire process (100K cycles
that the larger diameter (3.5mm) Nobel Replace implant system showed highest wear, 1k cycles qualification) was repeated at a 50N higher load. This protocol
endurance limit among the 3 implant systems whereas for almost same size was continued until a breach was detected. A comparison test was run on (4)
implants (3.25mm vs. 3.3mm diameter), the Biomet 3i implant exhibited higher industry representative implant systems (n=5). RESULTS: (14) of the (20) samples
endurance fatigue strength (by ~40%) compared to Straumann Bone Level resulted in a breach at the IAJ, whereas the remaining (6) samples breached
implant. CONCLUSIONS: Fatigue testing per ISO14801 on 3 different implant due to a structural failure. Sample failure loads ranged from 100N to 900N,
systems of comparable size from various manufacturers revealed that the representing an accumulation of 100k to 1.7M cycles, respectively. An ANOVA
slightly larger size Nobel Replace implant has the highest endurance limit with was conducted to statistically compare the implant system results. Three levels
BIOMET 3i Osseotite 2 implant showing higher endurance limit than the were established (p<0.0001), with a distribution of 1 system in a top bracket,
comparable size Straumann Bone Level implant. 2 systems in a middle bracket, and 1 system in the lower rank. CONCLUSIONS:
A new test method has been developed to qualitatively assess the seal
robustness of implant systems subjected to clinically representative cyclic
loading conditions. A future development step would likely include improved
quantification of the breach.

P189

Complications with Round Implants.

B.W. Renehan*, J. Grant Colorado Springs, CO.

The design of currently available implants emulate the root struction of the
anterior dentition. Conventional implants work well for replacing single rooted
teeth. The posterior detition has multi-rooted teeth with coresponding larger
clinical crowns. When round implants are used to replace molars, an
unanatomical emergence profile results. These larger than anatomically correct
spaces trap food and provide an environment for bacterial colonization, which
can be detrimental to the congruent natural dentition. By placing a titanium
platform in an alveolar osteotomy that is secured with a round implant, a
retoration with anatomically correct emergence profile may be acheived. Eleven
of these platform/implant combinations were placed over 3 months in 2009.

117

Poster Presentation Abstracts

This poster describes the surgical and restorative techniques as well as the two- observed. As they approached to the body of the component they changed
year clinical results of the first generation of this new clinical innovation. direction becoming perpendicular or oblique. In many samples signs of
insertion from these fibers directly to the prosthetic component were observed.
P190 All samples from this group presented perpendicular fibers originated from
bone crest “inserted” directly into the prosthetic component. Based on these
A Theoretical Analysis of Component-level Vertical Restorative Error. results it can be suggested that the bone maintenance coupled with increased
mechanical stability provided by the tapered interface allows the insertion of
R. Towse*, D. Ouellette, Z. Suttin Palm Beach Gardens, FL. collagen fibers directly to the prosthetic component, creating a stable soft tissue
barrier and providing protection to the bone crest.
OBJECTIVE: This assessment was conducted to investigate the potential
vertical location error attributable to the component interactions in a conically P192
shaped implant-abutment junction interface. MATERIALS AND METHODS: A
representative conical interface design was created with a 25 degree taper angle A Prospective Randomized-controlled Study of Endobon® Used in
(A), a 3mm coronal diameter (B), and a 1.25mm connection depth (C). Machine Extraction Sites: A Clinical and Histological Evaluation.
tolerances of +/- 1 degree and +/- 0.05mm were assigned for the angular and
linear dimensions, respectively. To determine the total range over which a single A. Barone*, M. Todisco, M. Ludovichetti, F. Gualini, D. Torrés, H. Aggstaller
component interaction could vary, extreme minimum (A=26, B=2.95, C=1.2) Palm Beach Gardens, FL.
and maximum (A=24, B=3.05, C=1.3) design condition scenarios were evaluated
for the mating geometries. Because the restorative paradigm involves several OBJECTIVE: This prospective randomized-controlled study compares the
sequential component mates (i.e., implant / coping, analog / coping, abutment quality of de novo bone generated in large tooth extraction sites after grafting
/ analog, and then the implant / abutment) throughout which vertical location with two brands of xenograft: Endobon® and Bio-Oss®. MATERIALS AND
error can accrue or diminish, a range of numerical test cases encompassing METHODS: Patients needing at least two tooth extractions in the premolar or
these process steps were conducted. The values for a single test system are molar regions on the same day are included in the study. The sites are randomly
presented in the table below. RESULTS: The vertical error value for the condition assigned to either a test or control group: Endobon (test) or Bio-Oss (control).
in which the maximum component was mated into the minimum component The grafted sites are covered with a resorbable collagen membrane
was +320µ. The vertical error for the opposite mating condition was -235µ. The (OsseoGuard) in order to avoid the loss or movement of any grafting material
accumulated vertical error for the numerical test case in the table was -55µ. without the need for releasing incisions to achieve marginal closure. After six
Additional test case outcomes will be presented demonstrating the potential months of healing, dental implants are placed. Graft maturation is assessed
array of accumulated vertical error results. CONCLUSIONS: There are multiple by the histological analysis of bone samples obtained from the grafted sites
factors (i.e., impression and casting materials / techniques, screw torques, during osteotomy preparation. Patients are seen thereafter every six months
surface finish, etc.) which contribute to the vertical location error during the for another two years to evaluate dental implant performance. RESULTS: At this
restorative process, one of which is the repeatability of the individual interim analysis a total of 39 patients are enrolled with 78 treated extraction
component interactions. While a traditional butt joint implant-abutment sites. A total of 66 bone cores were suitable for histological evaluation with
junction interface is essentially unaffected by component-level error because 30 from test sites and 36 from control sites. A total of 74 Osseotite or NanoTite
the mating of two planes controls the vertical location, it has been Tapered implants were placed and are being followed. The percent vital bone
demonstrated that a conical connection is prone to this additional error. for the test group is 29.10% and for the control group 27.31%. Because both
Consequently, further diligence is paramount during the design, production test and control cases are in the same patient all baseline variables are similar
and restoration of conical connection systems to minimize the vertical location allowing a comparison of performance and success rates between treatment
error. groups. All but one implant integrated successfully and a total of two implant
failures are recorded for an overall success rate of 97.3% at one year.
CONCLUSIONS: In this study, extraction sites treated with both types of bovine
xenografts were found to have de novo bone formation and provide a
functional anchorage for dental implant placement.

P191 P193

Histological Evaluation of Collagen Fibers Orientation around External Failing Anterior Teeth: An Interdisciplinary Approach.
Hexagon and Cone Morse Implants under a Polarized Light.
S. Siqueira*, P.P. Camara, M.M. Lobo, A. Stefani, S.P. Pimentel São Paulo, Brazil.
D.S.M. Castro*, A.R. Souza, C.M. Benfatti, R.F. Silva, F.H. Stancari, P.R. Conti,
G. Iezzi, A. Piatelli, M.R. Araújo, C.P. Araújo Bauru, Brazil. Rehabilitation of anterior teeth destined for extraction is complex and
requires a comprehensive and accurate diagnostic and treatment plan. It is
The presence of a functional and stable gingival tissue barrier around essential to consider the functional and esthetic aspects of the rehabilitation,
osseointegrated implants may provide greater biological protection to the bone and the patient’s necessities. The purpose of this case report is to describe three
tissue, for this reason, the presence of collagen fibers arranged in different cases that demonstrate the importance of the use of a multidisciplinary
directions seems to be important. This study aims to evaluate the presence and approach to successfully manage the rehabilitation of maxillary central incisors
orientation of the collagen fibers around two different implant types. 42 employing orthodontic extrusion and peri-implantar plastic surgeries.
implants were installed in seven dogs, 14 external hexagon (Osseotite - 3i, USA)
and 28 cone morse (CM Titamax EX - Neodent, Brazil), all received prosthetic
components, following the immediate loading protocol. After 4 months of
healing, the animals were sacrificed and samples were collected and processed
for histological evaluation by means of Exakt processing system. To assess the
direction of collagen fibers, 10 samples from each group were evaluated in
an optical microscope, under the incidence of polarized light. Around all the
samples from both groups, a well-organized collagen fibers network running
in different directions was found. Around the external hexagon implants, all
samples showed parallel fibers coming from the oral epithelium running parallel
to the prosthetic component and the implant neck. Above the implant platform
no perpendicular fibers were observed in any sample of this group. Usually,
collagen fibers approached the implant surface in an oblique or perpendicular
orientation and often became parallel to the implant surface. Six samples
showed perpendicular fibers below the bone crest, located around the implant
threads, and showing some “signs of insertion”. Around the cone morse implants
fibers arranged parallel to the upper portion of the prosthetic component were

118

Poster Presentation Abstracts

P194 and complications, chewing and overall satisfaction. The questionnaires were
given out and collected by trained dental assistants. Radiographic and clinical
Role of Perioperative Antibiotics in Replacing an Endodontically-treated measurements were also made at baseline and 12 months post treatment in
Tooth with a Dental Implant. both groups. The data was analyzed and compared over time and between the
2 groups. Results: All patients completed the 1 year follow up period. No failures
S. Bencharit*, E. Givens, C.R. Mack, B. Hosseini Chapel Hill, NC. or major complications were recorded in either treatment modalities. No
statistical significant difference in pain, complications, or overall satisfaction
Overprescription of antibiotics can lead to a bacterial resistance problem was noted between the two groups at any of the time points (p > 0.05).
in an individual patient, as well as in the general population. While most dentists However between the time points there were differences within each group.
often use antibiotics appropriately, overprescribing antibiotics in dental implant There was more pain at the pre-op for RCT and 7 day post op for IMP than
therapy is common. A majority of implant surgeons believe that antibiotics may any other time point. More complications were demonstrated at the 7 day post
improve clinical outcomes of implant therapy and prescribe antibiotics op than any other time point for both groups. There was no difference in the
unnecessarily. When a failure of endodontic treatment occurs in an overall satisfaction from any time point for either group. Conclusions: The results
anterior/premolar tooth, extraction and immediate placement of a dental of this study suggest that both treatment modalities have comparable
implant is often prescribed. The presence of a chronic periapical lesion resulting successful outcome. Patients perceived both treatments with high degree of
from an endodontic failure does not require antibiotics in most dental satisfaction with minimal pain and complications. Differences were found at
procedures, including extraction or endodontic re-treatment. Antibiotics are different time points of treatment, which were related to the nature of the
however frequently prescribed when immediate implant placement/loading is treatment itself. Understanding patient satisfaction and the way they perceive
performed. We hypothesized that the use of antibiotics, in conjunction with pain and complications can be helpful when explaining to the patient the
extraction and immediate placement/loading of a dental implant replacing a nature of the procedure, as well as when helping patients faced with treatment
failed endodontically-treated tooth without an acute infection, will not improve modality decisions.
clinical outcomes including postoperative discomfort, tissue changes,
microbial/proteomic profiles of peri-implant fluid and success/failure of dental P196
implant therapy. This study presents a preliminary report of patients with a
failed endodontically-treated tooth in the anterior/premolar area. Subjects were Evaluation of Immediate Provisionalized Implants in Sockets and Healed
randomly assigned to have either perioperative antibiotics or a placebo. Ridges after 3 Years.
Surgeons, patients, and restorative dentists were blinded of the group
assignment. The affected tooth was extracted. An implant was immediately L.F. Cooper*, H. De Bruyn, F. Raes, G. Reside, J. Soliva Garriga, L. Giner Tarrida,
placed and restored with a provisional abutment/crown. Subject were seen J. Wiltfang, M. Kern Chapel Hill, NC.
at 1, 2, 4, and 8 weeks post-operatively to assess the level of pain/discomfort,
and measure soft tissue changes. At 8-12 weeks the implant was restored with Clinical decisions regarding implant placement strategies for failing anterior
a definitive abutment/crown. Conebeam CTscans and impressions were maxillary teeth are multifaceted. The timing of extraction, implant placement
performed preoperatively and at 6 months after implant placement to assess and restoration is dependent on variables that remain incompletely defined.
the soft/hard tissue changes. The results suggest that the use of antibiotics in The goal of this 5 year prospective investigation is to better understand the
implant therapy may not be necessary to replace a failed endodontically-treated outcomes of immediate loading of implants placed into extraction sockets
tooth with chronic periapical lesion. versus healed ridges. Methods: Evaluation of 55 implants in extraction
sockets(group A), 58 implants in healed ridges (group B) and 23 implants in
P195 grafted sites (Group C)was performed 3 years following placement and loading.
All implants were placed in the anterior maxilla. Implant survival, marginal bone
The Success and Degree of Patient Satisfaction and Perception of level, gingival health, gingival zenith and papilla index measures were recorded
Complications with Non-surgical Root Canal Treatment or Delayed Single using standard clinical and radiographic measures involving peri-apical images.
Implant Treatment. A One Year Prospective Study. Results: The Kaplan-Meyer implant survival proportion was 0.95, 0.98 and 0.96
for Groups A, B and C. The change in marginal bone levels from implant
W. Salha* Fort Worth, TX. placement to 3 years was +1.6 (+/-2.4) mm, -0.4(+/- 1.5) mm, and -0.1 (+/-0.9)
mm for groups A, B and C. Importantly, at three years the established distance
Introduction: Dentists often face the choice of tooth retention with root from the marginal bone levels to the reference point was 0.7 +/-0.6mm, 0.8
canal treatment, or tooth replacement with implant treatment. To date there +/-1.1 mm and 0.7 +/-0.7 mm for groups A, B and C. The percentage of surfaces
has not been a prospective clinical trial directly comparing patient satisfaction with bleeding and plaque was low for the extraction and healed ridge groups,
and perception of complications of non-surgical root canal treatment to single but increased for the grafting group. Papilla were increased as evidenced by
tooth delayed implant treatment. Success rates were also compared between direct linear measurement for mesial papilla of groups A (0.2 +/-1.2mm), B
the two treatment modalities. Methods: 48 consecutive patients met the (0.6 mm +/-1.2 mm), and C ( 0.6 +/-0.9 mm) as well as distal papilla of groups
inclusion criteria. 24 patients had initial non-surgical root canal treatment (RCT A(0.4 +/-1.3mm), B (0.5 mm +/-1.0 mm), and C ( 0.5 +/-1.0 mm). Importantly,
group) and 24 had single tooth implant treatment in healed sites (IMP group). the gingival zenith scores showed positive changes for group A (0.2+-0.9mm);
Questionnaires were given at pre-treatment and at 7 days, 3, 6, and 12 months group B (0.2 mm+/-1.0 mm) and group C (0.5 mm +/-1.1 mm). Conclusion:
post-treatment. The outcome assessments included were perception of pain, The immediate loading of AstraTech OsseospeedTM implants in extraction
sockets and healed ridges display similar clinical performance at the
intermediate, three year follow up examination. As expected bone levels
increase at the extraction socket sites and the minor changes occurring in
healed ridges and grafted bone is consistent with previous data concerning
this implant. Irrespective of the group, the distance from the implant reference
point to the marginal bone level was consistent. Supported by AstraTech AB.

P197

Endosseous Bony Canals in the Symphysis using Cone Beam
Tomography.

B. Gupta*, M. Damouras, G. Dawits, G.E. Romanos Rochester, NY.

Purpose: The purpose of this study was to investigate the distribution of
endosseous bony canals in the anterior mandible using cone beam technology.
Materials and Methods: 299 CT Scan images based on Cone Beam Computed
Tomography (CBCT) of the anterior mandible were analyzed for the presence
of endosseous blood vessels. The vessels were observed in relationship to the
adjacent anatomical structures, and their topographic variability was analyzed
in relation to patient age and gender. Results: According to our analysis, the

119

Poster Presentation Abstracts

bony canals were found in the anterior mandible in almost 86% of the examined transferred by an internet based file transfer protocol. Additionally the
cases independent of age and gender. The highest regional frequency was seen conventional work flow was followed for the evaluation study. The shipment
in the midline area followed by the lateral incisor and canine region. The length of direct milled surgical guide was done from the center to the dentist. The
of the canals showed a range of 5 to 15 mm (mean of 10.55 mm). Multiple (2 clinical use showed that the surgical guides could be placed accurate on the
to 3) canals were also observed in approximately 9% of the scans. Variability residual dentition without any jiggling movements. The conventional surgical
in the appearance of these bony canals in the symphysis region was also guides were used as a control for the manual check of the deviation of the
demonstrated. Conclusions: The endosseous vessels in the symphysis were implant axis. On five patients with the placement of 18 implants a post-
found using CBCT scans. The CBCT seems to be an important diagnostic operative CB-CT scan was necessary, which allowed a matching of the pre-
technique for evaluation of the exact distribution of bony canals in the operative planning and the post-operative achieved implant positions. The
symphysis, region of the mandible and may reduce the risk of surgical average deviation for the crestal implant position in the xy-plain was 0.68 ±
complications. 0.28 mm and for the apical xy-plain was 0.92 ± 0.43 mm. The direct transfer
of the digital planning data by an internet based file transfer protocol allows
P198 the fabrication of surgical guides in a center without the need of a physical
transport which reduce the logistic and financial effort for the central fabrication
A Prospective, Randomized-Controlled Study of Implants Placed of surgical guides with a clinical known accuracy.
Simultaneously in Maxillary Sinus Augmentation Cases: A Clinical and
Histological Evaluation. CBCT-scan with superimposed optical impression for angled implant placement on
remaining periodontal compromised teeth
Z. Mazor* Palm Beach Gardens, FL.

OBJECTIVE: In this prospective, randomized-controlled study, implants
placed at the time of sinus augmentation with either of two bovine xenografts
to determine if a difference can be observed in implant success outcomes.
MATERIALS AND METHODS: Patients requiring uni- or bilateral- sinus lift
augmentations are randomly assigned to either a test or control xenograft
groups: Endobon (test) or Bio-Oss (control). An OsseoGuard membrane
(Biomet3i) is placed to cover the lateral sinus wall window. Implants (Biomet3i
NanoTite Certain Tapered) are placed during the augmentation surgery in a
two-stage surgical approach. The final prostheses are inserted at 8 months. For
cases where additional implants are placed after a healing period, augmented
bone is obtained for histological analysis. Implants are followed for up to three
years for assessment of function. RESULTS: At this interim analysis a total of
20 patients are treated and under observation with 60 implants placed, 34 in
test sites and 26 in control sites. All implants integrated successfully and remain
in function after an average of 26.4 months from placement for a 2 year
cumulative survival rate of 100%. Histological outcomes for six samples included
a 16.2% and 26.7% de novo bone formation for test and control sites
respectively. CONCLUSIONS: In this study, NanoTite Tapered implants establish
and maintain integration similarly in both Endobon and Bio-Oss treated
maxillary sinus augmented cases. Histological outcomes are also not different
but the samples size limits significance testing.

P199 P201

Soft Tissue Manipulation as an Adjunct to Guided Surgery in the A Prospective Observational Study of Immediate Loading Cases of
Posterior Mandible. Certain Tapered Implants.

P.J. Friel* Glasgow, United Kingdom. F. Capponi*, A. Muñoz, F. Fuentes Palm Beach Gardens, FL.

Computer guided implant surgery has been used for many years to OBJECTIVE: This study is designed to correlate the integration success of
successfully plan and place implants in positions with predictable accuracy. The immediately-loaded Osseotite Tapered implants and the insertion torque forces
process involves drilling sequences which allow for the flapless placement of recorded in their placement. MATERIALS AND METHODS: All study patients have
implants to a position predetermined by pre-surgical planning. In many of provisional restorations inserted within 48 hours of implant placement. All
the systems available, the drilling sequence involves initially drilling through implants (Osseotite Tapered implants, Biomet3i) are placed with a specific effort
crestal soft tissue to expose the bone surface beneath and in the posterior to record the insertional torque force as measured by a torque-indicating ratchet
mandible this invariably involves the obliteration of any remaining crestal wrench (H-TIRW, Biomet3i). The wrench is used to drive the implants allowing
keratinised tissue which can affect the long term prognosis of the implants in the recording of the insertion torque force at each 1 mm of the implant’s
that area. This study aimed to demonstrate concepts of soft tissue manipulation descent into the osteotomy and final seating. ISQ values are obtained at baseline
in the posterior mandible during the planning and execution of guided surgical and at definitive prosthesis insertion at 4 months. All implants are tested prior
techniques in the area, thus enabling the maintenance and propagation of to definitive prosthesis placement for integration success by counter-torque
remaining keratinised soft tissue around the definitive restoration. testing at 20 and 32 Ncm. Patients are followed clinically for 2 years. RESULTS:
At this interim analysis a total of 43 patients are enrolled with 86 study implants
P200 under evaluation. Insertions forces and ISQs were recorded and counter-torque
testing continues for recent cases. Two implants have been reported as failures
Digital Workflow for the Fabrication of CAD-CAM Manufactured Surgical for an interim CSR of 97.6%. Radiographic outcomes of crestal bone changes
Guides. will be reported and presented. Insertion torque profiles for all study implants
will be analyzed to determine if a correlation exists between implant insertion
F. Möller*, J. Neugebauer, M. Scheer, F. Kistler, S. Kistler, L. Ritter, T. Dreiseidler, variables and success outcomes. CONCLUSIONS: In this interim report, Osseotite
D. Rothamel, J.E. Zöller Landsberg, Germany. Tapered implants placed and provisionalized within 48 hours have integrated
successfully. A correlation between insertion torque values and implant success
The use of surgical guides for the implant placement which were produced will be explored.
in centers by CAD-CAM technology is increased due to the more frequent
availability of devices for 3D radiological diagnosis. The conventional workflow
requires a complex logistic chain which is time- and cost-intensive. Within a
pilot study, the workflow of direct milled surgical guides was evaluated on 20
patients with 63 implants. These surgical guides were designed on the fusion
of an optical impression and the radiological data. The planning data were

120

Poster Presentation Abstracts

P202 Interproximal Contact (IC) between implant prostheses and adjacent teeth.
Patients are selected into the study given that they have implant restoration in
Platform Switching Versus Conventional Technique - A Randomized the posterior or anterior region for at least 3months. Exclusion criteria consist
Controlled Clinical Trial. of prior open contacts that have been restored at least once after the delivery
of the prosthesis. This study consisted of 114 implant restorations in the
N. DeAngelis*, M. Nevins, M. da Costa Camelo, Y. Ono, M. Campailla Palm posterior or anterior region. Participants were evaluated ≥ 3months after
Beach Gardens, FL. implant restoration insertion and seen at random intervals to identify IC
openings. Cases were identified by using dental floss and factors leading to this
OBJECTIVE: A prospective randomized-controlled split-mouth multicenter phenomenon further investigated. Statistical tests were performed in order
study was done to evaluate the effect of platform switching on the preservation to determine incidence of and factors leading to IC loss. 114 implant restorations
of crestal bone. MATERIALS AND METHODS: Patients needing multiple were examined and 36 open contacts were identified. A larger sample size
restorations had their sites randomly assigned to receive either test or control will be presented in AO meeting.
implants. Test sites received NanoTite Certain Tapered Prevail implants that have
an integrated platform-switch feature and control sites have NanoTite Certain P205
Tapered implants. Intraoral radiographs are obtained with a paralleling
technique at abutment delivery, provisionalization, and after 6 months and 1 Influence of Modifications Nanotopography of Dental Implant Surfaces
year of loading. RESULTS: At this interim analysis a total of 78 study implants on Bone Proteins Expression.
are being followed with 41 test and 37 control cases. Many patients have both
test and control implants making the baseline variables for the two groups T.P. Queiroz*, R. Margonar, A.R. Guastaldi, R. Okamoto, A.P.S. Faloni, F.A.
evenly balanced for gender, age, and smoking. Average duration from implant Souza, I.R. Garcia-Júnior, E. Hochuli-Vieira Araraquara, Brazil.
placement to provisional loading is 5.1 months. All but one NanoTite-surfaced
implant integrated successfully and currently maintain function. Average crestal The success of dental implants depends on physical and chemical properties
bone loss for the Prevail platform-switch implants is 0.197 +/- 0.31 mm and of their surfaces which interfere with the biological response, including bone
for control implants is 0.597 +/-0.49 mm. Additional radiographic data will be proteins expression and consequently bone repair. Implant surfaces modified
collected at follow-up intervals to determine the long-term effects of this by laser beam (LS) with and without deposition of hydroxyapatite (HA) by
technique. CONCLUSIONS: In this study, platform-switched implants preserved biomimetic method, without heat treatment (HAnTT) and with heat treated
crestal bone more than implants with matched-abutment cases. (HATT) were compared to surface modified by acid (AS) and to machined
surface (MS). A topographical analysis of the implants was performed. Forty-
P203 five rabbits received 90 implants. After 30, 60 and 90 days, the animals were
killed. The implants were removed by reverse-torque and the sorrounding bone
A Prospective, Randomized-Controlled Evaluation of the Osseotite was processed and submitted to immunohistochemistry for detection of some
Certain Prevail Tapered Implants for Preservation of Crestal Bone. bone proteins, such as, core binding factor alpha1 (CBFα-1), osteoprotegerin
(OPG), receptor activator of NF-κB ligand (RANKL), osteopontin (OPN) and
M. Pavez*, M. Soriano Palm Beach Gardens, FL. osteocalcin (OC). The topographical analysis showed statistically significant
differences between the roughness of LS, HAnTT and HATT versus (vs.) AS and
OBJECTIVE: This prospective, randomized-controlled, split-mouth design MS. At 30 and 60 days, LS, HAnTT, HATT and AS reverse torque values were
clinical study evaluates the crestal bone preserving performance of the higher than those observed to MS. At 30 days, HAnTT and HATT reverse torque
Osseotite Certain Prevail Tapered implant system when compared to similar values were higher than AS and HAnTT was higher than LS. Moreover, at 90
implants that do not have a platform-switch feature. MATERIALS AND METHODS: days, HAnTT and MS were diferent from each other. Regarding to
Patients requiring multiple implants have the sites randomly assigned to receive immunohistochemical results, CBFα-1 immunolabelling revealed increased
a Tapered Prevail implant (Test) or a similar implant but with the implant seating staining at 30 and 60 days vs. 90 days for all nanotopography modified surfaces
surface and abutment each having the same diameter (Control). Implant (LS, HAnTT and HATT). The RANKL:OPG ratio tended to decrease over time for
insertion force is recorded using a torque-indicating ratchet wrench (H-TIRW, the treated surfaces vs. MS. HATT exhibited higher positivity for OPN and OC
Biomet3i). The wrench is used to rotate the implants into position recording at 30 days in comparison to 90 days. The physical and chemical modifications
the torque resistance at each 1 mm of the implant’s descent into the osteotomy were responsible for obtaining nanotopography implant surfaces which in turn
and final seating. ISQ values are obtained at baseline and at prosthesis insertion. accelerated the expression of bone proteins relevant to osseointegration.
Baseline radiographs obtained at implant insertion are made with a bite
registration technique that is used for all subsequent serial radiographs.
Radiographic outcomes are measured by one periodontist. Patients are followed
clinically for two years. RESULTS: At the time of this interim analysis a total of
41 patients are enrolled with 90 study implants under evaluation, evenly divided
between test and control cases. All but one implant achieved initial integration
and all other implants remain in function. Radiographic processing is underway
and outcomes for all implants will be presented. The insertion torque profiles
for all implants will be analyzed to determine if there is a correlation with
insertion variables and crestal bone regression outcomes. CONCLUSIONS: In
this study, Osseotite Certain Tapered Implants and Prevail implants have a high
integration rate. The split-mouth study design will allow a sensitive analysis
of the effect of platform switching for crestal bone preservation.

P204

Incidence of Interproximal Open Contact Related to Implant Placement
Posteriorly and Anteriorly.

S. Varthis*, D.P. Tarnow, A. Randi New York, NY.

The loss of Interproximal Contact between fixed implant prostheses and
adjacent teeth are frequently reported. This is significant since patients often
complain of food impaction. Chronic food impaction may lead to periodontal
defects and recurrent decay. In order to prevent implant periodontal sequelae
and tooth decay, a new proximal contact should be established between the
prosthesis and adjacent tooth. Due to a lack of sufficient research on this topic,
it is important to determine the incidence of Interproximal Contact loss and
identify the contributing factors of this phenomenon. Upon satisfying the
research, clinical guidelines can be established to prevent Interproximal Contact
opening. The aim of this study was to determine the incidence of open contact
in implant restorations and to identify the factors contributing to the loss of

121

Poster Presentation Abstracts

P206 cases. Insertions forces and ISQs were recorded and countertorques testings
were completed. A total of 9 implant failures are observed with 6 from the
Sinus Lift with BMP - A Prosthodontist’s Perspective. control group and 3 from the test group 94.9 and 97.5% CSR respectively. Only
a small number of implants were observed to rotate during counter-torque
A.P. Wadkar*, Y. Khanna Jersey City, NJ. testing. The insertion torque profiles for all test and control implants will be
analyzed to determine if there is a correlation with insertion variables and
Sinus floor augmentation using different grafting materials for increasing success outcomes. CONCLUSIONS: In this study, Osseotite 2 implants have a
alveolar bone height has been reported to be successful in clincal and scientific high integration rate as determined by countertorque testing. There is a possible
studies. Autogenous bone, freeze-dried bone, xenografts and alloplasts have correlation between insertion torque values and implant success.
been utilized in a variety of techniques. One such material being used as an
alternative to autogenous bone is human bone morphogenetic protein - 2 P209
(rhBMP-2). In this presentaiton the author wishes to educate us about the use
of BMP and it’s role in subantral augmentation procedures. The presentation The Effects of Desferrioxamine on Gene Expression for Different Implant
encompasses an extensive lierature review about sinus grafting with the use Surfaces.
of BMP. Finally, the author would conclude with a series of clinical cases in which
sinus augmentation was carried out with the use of BMP in combination with D.B. Mendonca*, G. Mendonca, L.F. Cooper Chapel Hill, NC.
a variety of graft materials and would elaborate on the future trends, prospects
that could lead to the modification and further development of this technique. Desferrioxamine (DFO) is a drug used for iron chelation therapy and acts as
a hypoxia-mimetic agent, blocking the degradation and inducing the
P207 accumulation of HIF-1α ( Hypoxia-Inducible Factor 1α), the main transcription
factor related to hypoxia. The importance of hypoxia in angiogenesis and bone
A 42-month Retrospective Study Using Immediate Implants in 508 formation have already been reported. The aim of this study was to investigate
Complete Arch Reconstructions Using the All-on-4 Technique. the effects of DFO on implant surfaces on osteoblast-related gene expression.
Methods: Human fetal osteoblasts (hFOBs) were grown on titanium disks (20
C.C. Butura*, D.F. Galindo Phoenix, AZ. x 1 mm) with machined (S), micron- (R) or nanostructured (N) surfaces immersed
in DFO solution overnight. Cell morphology on the different surfaces was
Introduction: Patients in need of full-arch implant reconstruction have analyzed by Scanning Electron Microscope (SEM). Real Time PCR was used to
traditionally been submitted to numerous surgical and prosthetic procedures. measure the mRNA levels of Runx2, Osx, HIF-1α, and VEGF after 1 and 3 days.
This series of cases seeks to illustrate a very predictable method for delivering Cells were also transiently transfected with an HRE (Hypoxia Responsive
full-arch immediate implant restorations using the All-on-4 technique. Materials Element)-driven luciferase reporter plasmid and seeded on disks to measure
and Methods:A series of 508 patients for a total of 767 complete arches were the hypoxia effect on those surfaces. Results: No difference in cell morphology
treated by the same surgical-prosthetic team during the course of 42 months. could be seen for the different implant surfaces in the presence or absence of
Selection criteria consisted of patients with edentulous arches, terminal DFO. After 1d Runx2 mRNA showed an up-regulation for R and N surfaces in
dentition and the desire for fixed implant-retained prostheses. Pre-surgical DFO, compared to S of 7.0- and 5.8-fold, respectively. A 10.7-fold induction was
prosthetic evaluation and work-up consisted of cone-beam CT studies, noted for N surfaces after 3d. Osx was up-regulated by 7.2- for N while a 5.2-
periapical radiographs, diagnostic mounted casts,intra and extra-oral and 2.4-fold induction was noted for R and S disks immersed in DFO after 1d.
photographic records and evaluation of smile line and lip to tooth After 3d, N group showed a 44.6- fold induction. For HIF-1α, a 2.2- and 2.5-
relationships.Surgical procedures were completed under intravenous anesthesia fold increase was observed for R and N DFO treated disks after 1d and a 4.1-
and delivery of a fixed full-arch acrylic prosthesis was completed with 3-4 hours. and 24.5-fold induction could be observed after 3d, respectively. For VEGF, an
The patients were placed on a strict follow-up protocol which included 10 up-regulation of 4.6 was observed for both R and N surfaces after 1d. After
day, 2 and 4 month visits. Cone beam CT and periapical radiographs were taken 3d, a 3.3- and 21.4-fold increase was observed for R and N disks, respectively.
to evaluate bone level around the healing implants. Final prostheses were made The luciferase assay showed higher HIF-1α activity at the HRE when the disks
using the NobelBiocare Procera® bridge procedure. Results:During this period were immersed in DFO. After 24 hours, 20.0-, 17.6- and 14.0-fold induction in
248 male and 260 female patients were treated for a total of 767 arches. A total HIF-1α activity at the HRE for S, R and N surfaces treated with DFO, respectively,
of 3036 Nobel SpeedyGroovy® and 155 Nobel Active implants were placed.Of was observed. Conclusions: Results suggest a synergistic effect of DFO and
this total number 164(21%) isolated maxillas and 81(11%) isolated mandibles nanotopography in stimulating osteoblast-related gene expression.
were treated.The combined double arch patients totaled 261(68%). Of the total
maxillary 425, arches 10(3%) had 1-3 three teeth remaining,47(11%) 4- 6 teeth P210
remaining and 259 (61%) more than 7 teeth remaining. Only 109 (25%) maxillas
were totally edentulous. Similar findings were observed in the mandible. Of the The Treatment of Alveolar Ridge Defects with Alloplast and Collagen
342 mandibular arches 15(5%) had 1-3 teeth, 69(20%) had 4-6 teeth and Membrane.
211(61%) had over seven teeth remaining. Only 47(14%) were edentulous.
The maxilla received 1751 implants and sustained 27 failures for a success are A. Fateh*, D.M. Kim, M. Camelo, M.L. Nevins, M. Nevins Boston, MA.
of 98.45%. The mandible received 1381 implants and sustained 3 failures for
a success rate of 99.78%. The overall implant success rate over the 42 month Introduction: Localized alveolar ridge defects present as a contraindication
time period was 99.04 % for a total of 3132 implants. A combination of 2977 for dental implant placement. A variety of materials and techniques with
Nobel SpeedyGroovy® and 155 Nobel Active® implants were placed. different degrees of success rates have been proposed to enhance clinician’s
ability to regenerate lost bone contour and volume. This case report evaluated
P208 the clinical and histological effectiveness of using an alloplast (combination
of hydroxyapetite (HA) and β- tricalcium phosphate (β- TCP), Osteon 2™) and
A Prospective, Randomized-controlled Study of Osseotite 2 Implant a collagen membrane (Bovine Type 1) to correct induced alveolar ridge defects.
Insertion Torque Values and Integration Outcomes. Materials and methods: Three patients in good health with no contraindications
to surgery agreed to be treated with multiple implant therapy, and have
A. Estefan*, D. Castro, C. Blanco, M. Gómez, R. Rios, J. Serrano, F. Vieira, M. volunteered for nonstrategic implant removal for a different study. The
Ferro Palm Beach Gardens, FL. procedure was thoroughly explained and the informed consent was obtained.
One posterior implant with surrounding tissue was removed in each patient
OBJECTIVE: This prospective, randomized-controlled clinical trial is designed using a piezoelectric surgical unit. Surgically created defects resembled a two-
to correlate the integration success of Osseotite 2 implants and the insertion wall defect (intact mesial and distal walls). Osteon 2™ (30% HA and 70% β-TCP)
torque forces recorded in their placement. MATERIALS AND METHODS: Patients was used to augment the defect, and the collagen membrane was used to cover
are randomized to either of two groups that have specific osteotomy the graft. Six month post surgical dental CT scans were made at the time of the
preparation procedures - an undersized osteotomy (Test) or a standard re-entry, and a bone core biopsy was obtained from each site. The osteotomy
osteotomy (Control). A torque indicating ratchet wrench is used to drive the was performed with a trephine bur to be able to evaluate the quality of bone.
implants allowing the recording of the insertion torque force at each 1 mm Results: All grafted sites revealed a significant amount of hard tissue formation.
of the implant’s descent. ISQ values are obtained at baseline and prosthesis The ridge contours restored close to their original ridge shapes. The regenerated
insertions. At eight weeks all implants are tested for integration success by sites appeared to be dense and well-incorporated with surrounding bone
counter-torque testing at 20 and 32 Ncm. Patients are followed clinically for 3 showing no signs of fibrous tissue ingrowth. Substantial amount of bone height
years. RESULTS: At this interim analysis a total of 60 patients are enrolled with
239 study implants under evaluation comprised of 121 test and 118 control

122

Poster Presentation Abstracts

and width formation was observed with visible graft particles on dental CT The constructs were evaluated at 0, 30, and 60 minutes for the ability to adhere
scans. Light microscopy revealed various amounts of graft particles, newly to the titanium implant and umbrella. Results: The results from all of the
formed bone and connective tissue from one specimen to another. Newly experimental groups showed no difference in gross morphology at 0, 30, and
formed bone bridged in between the remaining islands of Osteon 2™ particles 60 minutes post-placement for the adherence to the implant and umbrella. This
without any signs of inflammatory reactions. Conclusions: Results of a case runs counter to previous clinical experiences showing that increased proportion
report demonstrated the efficacy of using HA/β-TCP in combination with of allograft would result in a decreased adherence capability and stability of
collagen membrane for treating localized alveolar ridge defects. Clinical and the scaffold. Conclusions: In concert with DBM allograft’s established
radiographic evidence of bone regeneration was noted, as well as histological osteoinductive properties and the handling seen in this study, the authors
evaluation confirming the osteoconductive potential of the graft particles. propose that allograft can be used in higher proportions than previously
thought.
P211

Vertical and Horizontal Ridge Augmentation of Atrophic Posterior
Mandible using Combination Therapy.

D. Ho*, D. Kim Boston, MA.

INTRODUCTION: Vertical bone augmentation of severely atrophic alveolar
ridge remains to be a challenge in implant dentistry. Techniques such as onlay
block graft, guided bone regeneration, distraction osteogenesis and forced
tooth eruption have been attempted for vertical bone gain. However, these
procedures are associated with unpredictable outcomes and undesirable
complications. The aim of this report is to describe the combined use of
recombinant human platelet-derived growth factor-BB (rhPDGF-BB), titanium-
reinforced ePTFE membrane, and bone allograft/xenograft mixture without
tenting screws for vertical and horizontal bone augmentation in posterior
mandible. METHODS: Two patients with Seibert Class III posterior mandibular
ridge defects underwent bone augmentation using the combined therapy
mentioned. Mixtures of allograft (FDBA) and bovine xenograft hydrated with
rhPDGF-BB were placed on the ridges. Titanium-reinforce ePTFE membranes
were then placed over the composite grafts. Nine months later, CT scans were
taken and implants were placed at augmented sites. The quantity of bone
generated at the atrophic mandibles was evaluated by comparing the pre- and
post-operative CT scans. RESULTS: No soft tissue dehiscence and infection were
detected post-operatively. Post-operative CT scans taken at nine months
showed significant bone gain at previously atrophic ridges in both horizontal
and vertical dimension. There was an average bone gain of 4-6mm in height
and 8-10mm in width. The bone generated resembled type III bone as judged
when implant osteotomy sites were created. Ten-millimeter implants were
placed at augmented sites for all patients and implants are been restored.
CONCLUSION: Within the limits of this report, the combined use of rhPDGF-BB,
titanium-reinforced ePTFE membrane and allograft/xenograft provides an
alternative augmentation technique in achieving successful vertical and
horizontal bone gain at severely atrophic posterior mandible. This report
represents a pilot study on the combination therapy that should be investigated
more in-depth in larger populations.

P212

Differing Proportions of Bi-phasic Calcium Phosphate and Demineralized
Allograft in Scaffolds used for Dental Implant Bone Augmentation.

J. McNeish*, D. Ueno, D.M. Shafer, L. Kuhn, M.A. Freilich Farmington, CT.

Objectives: Growing bone height in the alveolar ridge cannot be done in
a predictable way. This in vitro study was a preliminary study of a translational
research program with many ongoing studies. Good handling characteristics
have been observed when particulate bi-phasic calcium phosphate scaffold
material is combined with blood at the local site, although this combination
has no osteoinductive capabilities. To maximize osteoinductive capabilities,
allograft could be used, although particulate allograft lacks enough body to
adapt well to the implant or bone. The purpose of this study was to determine
the optimal proportion of bi-phasic calcium phosphate and demineralized
cortical bone allograft used in combination for vertical alveolar ridge
augmentation. Methods: An infrabony defect Sawbones model was used to
evaluate the in situ effect of different proportions of bi-phasic calcium
phosphate and DBM allograft on the resulting particulate scaffold’s ability to
adapt to the titanium of the implant and bone. The bi-phasic calcium phosphate
and DBM allograft are commercially available and FDA approved for use in
the jaw. Five proportions (all n=5) were used: 1) 100% allograft; 2) 100% SBC;
3) 50% allograft 50% SBC; 4) 75% Allograft 25% SBC; 5) 25% allograft 75%
SBC. For each construct, 3 mL of blood from a laboratory mouse was used to
mimic the surgical procedure. Each proportion was then placed around the
supracrestal part of the implant underneath the umbrella in the posterior
mandible. The umbrella is a scaffold stabilization device that retains the 3D
scaffold and prevents soft tissue flap collapse, creating a space for bone to grow.

123

Poster Presentation Abstracts

P213 is a useful component which can acquire impression accuracy equivalent to
PUI.
Comparison of Peri-implant Hard and Soft Tissue Adaptation in Different
Implant Systems. P215

N. Saghafi*, M. Rowan, J. Pi-Anfruns, G. Ivry, T. Aghaloo, P. Moy Beverly Guided Implant Surgery: What is the Influence of this New Technique
Hills, CA. in the Immediate Bone Cells Viability?

Background: Peri-implant hard and soft tissue adaptation is important in R. Margonar*, P.L. Santos, T.P. Queiroz, A.C. Carvalho, R.L. Okamoto,
determining success of an implant and is especially important in the esthetic A.S. Faloni, I.R. Garcia Júnior Araraquara, Brazil.
zone. The microgap at the implant-abutment interface allows for colonization
of bacteria, and may cause early crestal bone loss and consequently affect The use of technologies that merge CT x-ray imaging and 3D planning
the interdental papilla. The 3D position of the implant is another determinant softwares allow the surgeon to digitally elaborate on the computer the position,
in formation of the papilla. Different implant designs and the concept of length and diameter of every implant to be placed. However, issues such as
platform switching have been developed to move the microgap away from the bone heating remain uncertain In this study, simulations of classical and guided
crest of bone in an attempt to minimize bone loss. Purpose: Evaluate the effect surgical techniques were performed to compare their effect on immediate bone
of microgap and design in different implant systems on the level of bone loss cell viability. Twenty rabbits were equally divided into two groups: control (CG)
and papilla fill in implants in esthetic areas. Method: In this retrospective study, and guided surgery (GG). To test the influence of re-using the same drills for
43 implants in the esthetic zone (#6-#11) in 32 recall patients will be evaluated. 10, 20, 30 and 40 times, CG and GG were divided into four subgroups: G1, G2,
All implants are placed by a single oral surgeon. Standardized, digital peri-apical G3 and G4, respectively. The animals received 5 osteotomies in each tibia by
X-rays were used to measure vertical distance from the crest of bone to contact using classical and guided surgeries. Osteotomized areas were collected and
point and horizontal distance from implant to tooth. To evaluate the soft tissue, processed for paraffin embedding. Bone sections were submitted to
intra-oral photographs were used and papilla scores were assigned according immunohistochemistry for Osteoprotegerin (OPG), Receptor Activator of
to Ryser et al. The implant systems evaluated in this study were Brånemark Nuclear Factor ΚB (RANKL), Osteocalcin (OC) or caspase-3 (cas-3) detection.
Mk III, Replace Tapered Groovy, Replace Select, and Astra. Results: Preliminary Immunohistochemical analysis showed similarity in the expression of proteins
data analysis on Brånemark Mk III (n= 8) and Replace TG (n=16) systems showed associated with the osteoclast formation and activity, such as OPG and RANKL,
no statistically significant difference in crestal bone level between the two for CG and GG. The expression of OC, was more intense in the CG, remaining
groups (4.8 and 5.5 mm respectively, P=0.13). The distance between tooth constant after re-use of the drills. The expression of cas-3 was balanced in the
and implant in the two groups was also statistically similar (2.6 mm in Mk III different GC subgroups, whereas an increased expression was proportional to
and 2.3 mm in Replace TG, P=0.61). Furthermore, the average papilla score was the increase in the number of osteotomies, in GG subgroups. This event
statistically similar in the 2 groups (3.5 in MKIII and 3.3 in Replace TG, P=0.68). indicates an increase in cellular apoptosis. Based on these results, it is possible
Although not statically significant, we found a higher percentage of complete to conclude that the classical technique favors cellular viability when compared
papilla fill in Replace TG (62%) compared to Mk III group (50%). Additional data to guided technique.
analysis on Astra and Replace Select is in progress and will be added to the
results. Conclusion: The preliminary results of this study show that the implant
system, in this case external (MkIII) Vs. internal (Replace TG) connection does
not have a significant affect on crestal bone loss or papilla fill. Further analysis
is in progress to compare other implant systems and to include a larger sample
size.

P214 P216

Comparison of Impression Accuracy by Different Types of the Impression Predictive Value of Resonance Frequency Analysis in Surgical Placement
Copings. and Loading of Implants of Various Systems.

T. Honma*, S. Muraoka, S. Hanada, T. Takeshita Tokyo, Japan. S. Baltayan*, M. Mardirosian, M. El-Ghareeb, J. Pi-Anfruns, T. Aghaloo,
P.K. Moy Los Angeles, CA.
Recent years, although it has become popular to use new transfer type
impression coping with a cap (TIC) which can reproduce direction of the The purpose of this study is to determine the predictive value of Resonance
abutment connection part and get high impression accuracy, it is considered Frequency Analysis in surgical placement and loading of various implant
that the positive impression taking with TIC may be difficult depending on systems. A retrospective study was performed on implant patient data collected
the angle of implant placement. In this study, we compared the impression over five years, with all implants placed by a single surgeon. Placement and
accuracy of TIC and that of the pick-up type impression coping (PUI). The master loading strategies were determined by the clinician and RFA values were
model was designed to hold three implant analogues so that implant analogues recorded with Osstell. 655 implant cases were used to analyze ISQ values at
could be set at a 20° and a 25° angle from one another. Three implant analogs placement: 109 were 3i, 374 were Branemark, and 172 were ITI. 1067 cases were
were inserted into the master model and fixed with screws from side to hold used to analyze ISQ values at loading: 144 were 3i, 618 were Branemark, and
in position. For impression taking, vinyl silicone impression material 305 were ITI. Acquired ISQ values were analyzed using receiver operating
(EXAIMPLANT, GC) was used. For gypsum model, super-anhydrite of a low characteristic statistics. Analysis demonstrated optimal ISQ cutoff values of 66
dilatability (NEW FUJIROCK IMP, GC) was used. Three impression copings of PUI for placement and 64 for loading, maximizing sensitivity and specificity. For ISQ
and TIC were installed in the master model respectively, and we took impression
and made the gypsum model by assuming it to be inside of the mouth. The
position of implant analogs were measured in three axes (x, y, and z axis), and
the error of the master model and the gypsum model was calculated. Moreover,
in a 20° master model, it was examined on three conditions; (1) without artificial
tissue, (2) with 2mm-thick artificial tissue, (3) with 4mm-thick artificial tissue.
For artificial tissue, vinyl silicone impression material (SILFLEX, Elephant Dental
B.V.) was used. In a 20° master model, accuracy of the impression coping are
x = 9.4 ± 4.4 µm, y = 15.1 ± 2.1 µm, and z = 11.0 ± 1.6 µm in PUI, and x = 10.0
± 2.5 µm, y = 13.9 ± 7.9 µm, and z = 10.9 ± 5.2 µm in TIC. There was no significant
difference of impression accuracy in a 20° master model. However in a 25°master
model, the dimensional change of the direction of a y-axis of TIC (y = 1.36 ± 2.5
µm) was significantly different from that of PUI (y = 52.3 ± 2.6 µm) (p<.05). There
was no significant difference of impression accuracy by the existence or the
thickness of artificial tissue. TIC is a component which can locate the direction
of the abutment connection equipment of the implant placement by simple
operation compared with PUI. Also, if the angle of the implant is not severe, TIC

124

Poster Presentation Abstracts

values above these cutoffs, clinicians could accelerate treatment and sustain control tubes in the first 24 hours. In the second step, three samples presented
the highest survival rates with confidence. In one-stage placement, implants positive results for bacterial leakage during the period of 14 days, which two
with ISQ values below 66 had a 94.5% survival rate and above 66 had a 100% were from the T10 group and one from the T20 group. After this period all
survival rate. In two-stage placement, ISQs below 66 had a 96.3% survival rate the samples presented viability for the bacterial test. Within the limitations of
and above 66 had a 100% survival rate. In early loading, ISQs below 64 had a this study, it was concluded that the torque value influenced the HE implants
94.9% survival rate and above 64 had a 99.0% survival rate. In traditional loading, bacterial microleakage and that the standardization of the test methodology
ISQs below 64 had a 95.6% survival rate and above 64 had a 99.9% survival rate. offered lower operator variables.
Comparing three implant systems for one-stage placement, if ISQ values are
below our cutoff of 66: 3i implants had a 90.5% survival rate, Branemark P219
implants had a rate of 91.7%, and ITI implants had a rate of 98.7%. For two-
stage placement, if ISQs are below the cutoff of 66: 3i had an 87.1% survival Vertical Ridge Augmentation Procedure using Autologous Bone for the
rate, Branemark had a rate of 97.5%, and ITI had a rate of 100%. Comparing Placement of Endoosseus Implants.
three systems for early loading, if ISQ values are below our cutoff of 64: 3i
implants had a 50% survival rate, Branemark implants had a rate of 93.1%, V.A. Umanzor*, I. Flores Mexico, Mexico.
and ITI implants had a rate of 100%. For traditional loading, if ISQ values are
below the cutoff: 3i implants had an 84.4% survival rate, Branemark had a 95.4% Introduction: One of the most important factors for the placement of dental
survival rate, and ITI had a 98.4% survival rate. When ISQ values were above implants is the availability of sufficient bone to support and retain the
optimal cutoffs, implant survival rates reached 100% for placement and loading. endoosseus implant. A variety of surgical procedures have been proposed to
The study shows RFA is a reliable method for determining placement and correct these ridge deficiencies; resorbable and non resorbables membranes,
loading protocols. The evidence shows it strongly predicts implant survival. graft materials and growth factors. As has been described in the literature,
autogenous bone is the gold standard for grafting, either particulated or as a
P217 block graft. Particulated bone is indicated when the area to be reconstructed
is reinforced by a membrane and can be harvested from different intraoral sites
Radiographic Bone Density around Dental Implants with Surface (mandibular symphisis, ramus and maxillary tuberosity). Guided bone
Modification by Laser Ablation followed by Hydroxyapatite Coating: A regeneration procedure has become a major treatment option to provide
Study in Rabbit Tibiae. optimal support for osseointegrated implants. Purpose: This case report shows
a partially dentate patient with a ridge deficiency Class C-M (Wang 2002) in
T.S. Cazelato*, R. Spin-Neto, J. Morais, L. Schropp, A. Wenzel, E. Marcantonio whom guided bone regeneration was performed using autogenous bone from
Jr, R.S. Faeda Piracicaba, Brazil. the mandibular symphisis with a 6mm wide trephine and the graft was later
grinded using a bone mallet. The graft was placed at the recipient site and
Surface chemistry seems to affect peri-implant bone healing, increasing covered with a titanium-reinforced polytetrafluoretylene (e- PTFE) membrane
bone-to-implant contact and biological and mechanical properties. The present fixed with screws. A reentry procedure was performed at 4 months later and
study aim to assess the radiographic bone density around implants with two acid-etched, sandblasted implants were placed. Results: At membrane
different surface treatment, comparing a surface treated by laser ablation removal of the e-PTFE membrane due to exposure, a free gingival graft was
followed by hydroxyapatite coating with a surface that was oxide-blasted placed as an onlay to augment the keratinized tissue. A reentry procedure
followed by acid etching. On this study twenty-four rabbits received two was performed at 4 months and measurements were taken. There was a vertical
implants in each tibia, an oxide-blasted + acid-etched (ATS) and a augmentation gain of 4 mm and a 2mm horizontal augmentation at the site.
hydroxyapatite-coated (HAP) implant. Radiographs of the implants were The implant survival rate was 100% at the site. Conclusion: Vertical
recorded after 4, 8, and 12 weeks of healing (8 animals in each healing period), augmentation with e-PTFE membranes and particulated autografts is a safe
and bone density was assessed in regions of interest (ROI) in cortical and and predictable procedure and can lead to long term success. Implants placed
cancellous bone adjacent to the implant using the shade of grey in the bone in vertically augmented bone by GBR technique may be similar to those placed
ROIs compared to a reference ROI in each image (a ratio was calculated: bone in native bone.
ROI/reference ROI). The data analysis indicated that the difference between the
density ratios obtained for both HAP and ATS implants were statistically non-
significant in all healing periods. In the ATS group, the ratio increased from week
4 to week 8 and then decreased from week 8 to week 12, in both cortical and
cancellous bone. The HAP group showed an increase in the ratio from week 4
to week 12 in cancellous bone while in cortical bone no variation throughout
the healing periods was seen. Based on the results, the HAP-coated implant
surface was not able to significantly increase the radiographic bone density
around implants compared to conventional ATS implants.

P218

Bacterial Microleakage in Hexagonal Implants at Implant/Abutment
Interface with Different Tightening Torque In Vitro.

T.D. Carneiro*, M.S. Prudente, J. Silva-Neto, M.A. Penatti, F.D. Neves
Uberlândia, Brazil.

The aim of this study was to evaluate the microleakage of abutment/implant
interface (A/I) in external hexagon implants (HE) with different torques values.
Nine HE implants extern torque with conical abutments and screws were
randomly selected and divided into three groups: V0.5, V1.0 and V1.5 and used
in two experimental steps. A Escherichia coli bacterial suspension (BS) was
prepared to the density of 0,5 McFarland standard and inoculated in the inner
parts of the implants. The clarity of the broth was observed each 24 hours
during 14 days, and after this period, the bacterial viability was checked by a
microbiological test. In the first step, implants were inoculated as follows: V0.5-
with 0.5 µL of BS; V1.0- with 1.0 µL of BS; and V1.5- with 1.5 µL of BS. Then
the abutments were wrench following the manufacturer’s recommended torque
values. In the second step, the experiment design was repeated three times for
checking the reproducibility and the assemblies were divided into three groups
with different torques values: T10- abutments wrench with 10 Ncm; T20- wrench
with 20 Ncm and T32- wrench with 32 Ncm. The results showed that in the first
step all the samples of V1.0 and V1.5 groups presented cloudy broth on the

125

Poster Presentation Abstracts

P220 P222

Radio Frequency Analysis in Correlation with Postoperative Bone Density Forced Eruption and Root Submersion before Immediate Implant
Measurements using Cone Beam Computerized Tomography. Replacing Upper Central Incisors.

M. Mardirosian*, S. Baltayan, P. Shiffler, A. Keuroghlian, T. Aghaloo, P.K. Moy R. Limberte*, C. Fornazari, P. Caetano Sao Paulo, Brazil.
Woodland Hills, CA.
Anterior hard and soft tissues deformities caused by fractured teeth are
Studies have shown a positive correlation between preoperative bone an aesthetic challenge in implant rehabilitation treatment in anterior zone. The
density, fastening torque, and implant stability. RFA has been found to be a labial plate resorption and the compromised gingiva very often reduce the
reliable method for determining placement and loading protocols. This study previsibility of the esthetic result. The forced eruption technique can change
is one of the very first to observe these correlation immediately post implant the implant site in immediate implant placement cases, changing both gingival
placement. The purpose of this study is to determine the correlation between soft tissue profile and the three dimensional osseous topography in the fresh
implant initial stability using Radio Frequency Analysis and post-operative bone socket. The creation of better conditions in alveolar bone will improve the
density from cone beam computerized tomography (CBCT). A retrospective esthetic result. The root submersion is an old technique to preserve the alveolar
study was performed on implant patient data collected over a one-year period ridge for complete dentures treatment for better retention. The tooth is
(2009) from a single surgeon in private practice. A total of 84 patients and 149 prepared until reach the bone level in order to create a condition for soft tissue
implants were selected to analyze RFA and postoperative Hounsfield formation and alveolar bone preservation around the root. The purpose of
measurement taken from CTs immediately after placement. RFA measurements the poster is to show that forced eruption and root submersion, in a simplified
were taken at 4 locations around each implant: buccal, mesial, lingual, and distal. protocol, can work together optimizing the esthetic and functional results in
Bone density analysis was done on post OP CT scans for each implant at the upper central incisors implant rehabilitation, with Nobel Biocare Replace Select
same 4 locations. 149 implants were measured for RFA and Hounsfield bone implants and zirconia abutments.
density. Average RFA values were 69.6 with a range of 35 to 88. Hounsfield
measurements at mesial locations were on average 739, distal locations were
599, buccal locations were 1138, and the lingual locations were 981. Correlation
analysis was done per location and showed only a mild correlation between
buccal and lingual sites. This study showed a very weak correlation between
bone density around implant and RFA value when measured on a CT. RFA
remains the reliable method for predicting initial implant stability. The use of
bone density measurements off of CT scans show weak correlation and was
not found to be a good predictor of implant stability. Bone density may be used
as a determining factor for timing of loading but can not be used as a predictive
factor of stability.

P221

Placement of Dental Implants in the Esthetic Zone Previously Treated
with a Ridge Augmentation Procedure using Guided Bone Regeneration.

E. Valle*, I. Flores México, D.F, Mexico.

Introduction: A prerequisite for implant placement is the availability of
sufficient alveolar bone to support and retain the implants. The use of ridge
augmentation procedures to enable implant placement using guided bone
regeneration with autogenous grafts widely considered the gold standard for
the correction of ridge deformities. However, the morbidity associated with
graft harvesting often limit treatment recommendations and patient
acceptance. Complications associated with grafts harvested include nerve injury,
soft tissue injury, wound dehiscence, and infection. The use of deproteinized
bovine bone as the filler material with the use of expanded
polytetrafluoroethylene, either in combination with autogenous bone or by
itself, has shown good and reproducible results in a variety of bone
augmentation procedures, or reduces complications. Materials and Methods:
A partially edentulous patient in whom atrophic edentulous anterior ridge was
submitted to a ridge augmentation prior to implant placement. The technique
was performed through the use of a titanium-reinforced expanded
polytetrafluoroethylene (e-PTFE) membrane with a mix of deproteinized bovine
bone (Bio-Oss) and demineralized freeze-dried bone allograft (DFDBA). After
5 months was placed 3 implants bone level SLActive with a model of
stereolithography. Results: At membrane removal, mean vertical augmentation
was 5mm. Mean combined crestal remodeling was 1.01mm at 10months. After
4months of ridge augmentation procedure, a exposure of membrane was
presented, that situation was controlled before placed implants. The range of
survival of implants was of the 100%. Conclusions: Ridge augmentation with
e-PTFE membranes and particulated allografts and xenografts is a safe and
predictable treatment. Success and survival rates of implants placed in a ridge
augmented bone with the guided bone regeneration technique appear similar
to implants placed in native bone under loading conditions.

126

Poster Presentation Abstracts

P223 monoclonal antibody which binds to receptor activator of nuclear factor- kappa
β ligand (RANKL) thereby interfering with the maturation of osteoclasts.
Block Grafting of the Mandibular Symphysis and Posterior Placement Understanding the latest data involved with this drug class is important in that
of Implants with Elevation of the Maxillary Sinus Floor. there have been reports of osteonecrosis of the jaw occurring in patients treated
during clinical trials for cancers affecting bone. In 2007 the American Heart
V.E. Hernandez*, M. Lopez Mexico, DF, Mexico. Association issued a statement recommending judicious and short term use of
nonsteroidal anti-inflammatory drugs (NSAIDS). Observational data involving
Autogenous bone grafting is a well documented procedure for 83,675 patients with history of a previous myocardial infarction (MI) has been
reconstruction of the atrophic maxilla and mandible for restoration with implant reported which shows that even the short term use (one week) of NSAIDS
prostheses. The symphysis of the mandible has been used extensively for onlay significantly increased the risk of death or a second MI in this group of patients.
bone grafting The presence of a maxillary sinus with severe pneumatization and The implications of this data must be understood in relation to pain
alveolar bone loss makes it difficult to install implant fixtures at the optimal management in patients with a history of cardiovascular disease undergoing
length, diameter, and shape, requiring further surgical intervention. There are implant therapy.
2 choices for the surgical procedure: window opening and osteotome technique.
Implants can either be inserted simultaneously, when there is sufficient bone P225
height for primary stability (±4 mm), or can be inserted in a second procedure
when bone-remodelling of the graft has taken place. This two stage procedure Clinical Evaluation of a New Implant Design in Conjunction with Sinus
is indicated when no good primary stability can be expected (bone height° 4 Lift Procedure: A Case Series.
mm). Materials and Methods: Female patient with sixty years old and no history
of systemic deseases with partial edentulous we perform a procedure putting T. Dinato*, J. Dinato, M. Groisman Porto Alegre, Brazil.
a block grafting of the mandibular symphysis and 4 months later we procedure
window opening and we inserted implants simultaneously. Procedure Technique Introduction: Maxillary sinus augmentation has proven to be a predictable
1)The operative area was reached by means of a fullthickness flap. 2)The procedure to correct bone deficiencies for implant placement with long-term
osteotomy line is made by cutting and dispersing the osseous table in a outcome. Implant stability in this situation is limited by residual bone quantity
controlled way. The ultrasonic tip of the device enables an increased tactile and quality as well as implant design. The aim of this study was to evaluate the
control and avoids soft tissue damage. A complete osteotomy along the clinical effect of the combination of sinus lift procedure with the installation
perimeter of the osseous window is initiated and deepened until tactile sensation of a new implant design to improve, among other factors, its primary stability.
of the schneiderian membrane. 3) Door is luxated inward and upward with the Methods: A total of 14 patients having missing teeth in the posterior maxilla
membrane to a horizontal position forming the new sinus bottom. 4)The space took part in the study. Cone beam CT images showed height equal or inferior
underneath this lifted door and sinus mucosa is filled with xenograft to 4 mm of remaining bone. Following 15 lateral window sinus lift approach,
material(1gr). 5) We place 2 implants nobel biocare with diameter 4mm for 13 anorganic bovine bone matrix graft material (Bio-oss, Geistlich, Wolhusen,
mm of length. Results: After 4 months of the placement of block grafting of Switzerland) was used for sinus lifting application. 27 CM Drive implants
the mandibular symphysis we gained 4 mm from horizontal bone ridge (Neodent, Curitiba, Brazil) were installed. Implant mobility, periimplant soft
augmentation, in the second procedure we have a primary stability (5mm) and tissue inflammation and bone loss measured at the CT images were the used
we gained 8 mm with optimal primary stability of the implants. Conclusions: evaluation parameters. Results: 5 implants were placed simultaneously with the
Horizontal bone ridge augmentation are a predictable technique and the sinus lift procedure and 22, 5 to 6 months later. All the implants installed had
elevation of maxilar sinus floor give us the posibility of placement of the implant 13 mm of length and 4.3 mm of diameter. The CM Drive has a tapered implant
with the optimal length, and diameter, and this represents a predictable design with sharp, widely spaced and gradually expanding threads, what led
technique. to a minimal initial implant stability of 35 N/cm and a mean initial implant
stability of 45.55N/cm. The implants were loaded 5 to 6 months after installation.
6 implants and their respective prosthesis were followed for a period of 12
months and 12 implants for a period of 6 to 12 months. Therefore, the present
study points out to a survival rate of 96.3%, with 1 implant lost and later
replaced. Inflammation was not observed at the periimplant soft tissues during
the entire study. Marginal bone loss was not observed around the implants
neck, analyzed by CT images. Conclusions: Within the limits of this clinical report
it may be concluded that maxillary sinus augmentation in combination with
the use of the CM Drive implants is a predictable clinical procedure. Further
studies are necessary to elucidate the long-term outcome of this combination.

P224

Recent Pharmacologic Issues which Affect Implant Dentistry.

W.B. Parker* Fort Lauderdale, FL.

The introduction of a new class of anticoagulants, a new class of drugs used
for osteoporosis and cancers involving bone, and recent studies regarding the
safety of nonsteroidal anti-inflammatory drugs will have significant effects on
our treatment of patients receiving implant related procedures. The use of direct
thrombin inhibitors (e.g dabigatrin (pradaxa™) is becoming more popular
amongst cardiologists for use in patients undergoing long term anticoagulant
therapy and is replacing warfarin which has been used for a number of years.
In that there is no therapeutic drug monitoring readily available for the direct
thrombin inhibitors and that there is no medication to reverse their effects, our
management of these patients must be significantly modified from the
guidelines we used for patients taking warfarin. Also a new class of medication
used to treat osteopenia, osteoporosis, and cancers affecting bone has recently
been approved for use. Denosumab (prolia™ and xgeva™) is a human

127

Poster Presentation Abstracts

P226 sectioned, glued on the glass slides and stained using H&E stain. On microscopic
observation, typical bone histology was observed. Active osteoblasts and bone
Results after 5 Years of the Kricheldorf Technique® - Minimally Invasive marrow were seen. Histomorphometrical analysis demonstrated 56% area
Surgery - For Vertical and Horizontal Increase of Severely Atrophic covered with bone. 100% of the bone was vital. No graft remnants were
Posterior Mandibular Alveolar Ridge. observed. Implant was placed and observed for a duration of 1 year. Implant
osseointegrated and functioned well. Conclusions: There is increasing interest
F. Kricheldorf* Joinville, Brazil. in bone graft materials that stimulate bone formation rather than the ones that
replace the lost bone. In this study, histological slide was prepared using the
Bone Graft surgeries has been severely discussed by various authors in cases longitudinal cross-section of the entire core and was studied to quantify the
of implants areas for single or multiples teeth. Along decades many materials amount of bone. Additionally, most of the previous studies were conducted on
and surgical technics were presented as a solution for many defects. But, there smaller anterior extraction sockets. In this report, larger molar extraction socket
is a big difficult to indicate a predictable, simple and painless surgical procedure was grafted with nCS. In spite of these facts, 56% area was covered with lamellar
in those atrophies. Alternatives for increasing vertical and horizontally atrophies, bone. The results indicate strong potential of nCS based bone graft for
specially in posterior area in lower jaw, such as bone distraction, inferior alveolar extraction socket grafting.
nerve dislocation, autogenic and allogenic graft, rh-BMP’s and short implants
present a series of prerequisites and the results show a satisfactory resolution
in those cases. Situations such as fibrosed tissue (intra-oral bone distraction),
inferior alveolar nerve damages, complications such as postoperative infection
and loss of graft (bone transplant), material costs have been frequently
described through the international casuistry. This paper will present a five years
follow-up using Kricheldorf Technique®, which consists of a vertical and
horizontal reconstruction of the remaining alveolar ridge specially in posterior
areas on mandible. Through a simple surgical technique, implants could be
inserted in an adequate place and complying with the standard technical norms
for its installations in posterior mandibular areas, respecting many postulates
of Spee’s and Wilson’s curves, having an adequate implant-crown
proportionality. Although, having as main characteristics the reduced surgical
time, small incision, original mucoperiosteal “bed”, without any fibrotic
alterations and a wide space for implants without any difficulties in this critical
area. As a part of this study, simple and critical cases will be presented with a
protocol, according to the research rules from ethical committee for a new
surgical procedure, support with a large histological analyses as well. As a
conclusion, the Kricheldorf Technique® can be used without any great difficulties
by dentist who has basics knowledge of surgical principles and offer a new
purpose of treatment to the patients with different kinds of atrophies by a
predictable, simple and painless results contributing for new challenges
developing of implantology.

P227 P228

Novel Nano-Crystalline Calcium Sulfate Based Bone Graft for Molar Bone Augmentation Procedure followed Implant Placement in the
Extraction Socket Augmentation. Esthetic Zone.

S. Mamidwar*, R. Horowitz, Z. Mazor, N. Tovar, I. Chesnoiu-Matei, J. Ricci M.P. Santiago*, R. Neria México, Mexico.
Springfield, NJ.
INTRODUCTION: Early implant placement is one treatment option for
Introduction: Presence of vital bone in the extraction sockets is important implant therapy. Today single- tooth replacement with an implant- supported
for the placement of dental implants. Various available grafts have certain crown has become the most frequent indication for implant therapy shorten
advantages and disadvantages. Hence the search for ideal bone graft continues. the overall treatment time and to minimize the number of surgical interventions
Calcium sulfate is biocompatible, biodegradable and osteoconductive. It is the to increase the attractiveness of implant therapy for patients, alternative
only graft that has angiogenic, barrier and hemostatic properties. To overcome approaches have been proposed, such as immediate implant placement at time
its fast degradation, nanocrystalline calcium sulfate based product that of extraction or early implant placement, which includes a few weeks of tissue
undergoes controlled degradation was developed. Methods: A female patient healing prior to implant insertion. PURPOSE: The purpose of this case was to
presented in the clinic with failing implant in site #30. Implant was placed 2 augment the facial bone wall with guided bone regeneration, using a titanium-
years. Implant was removed from the site. Socket augmentation followed by reinforced expanded polytetrafluoroethylene (e-PTFE) membrane and a bone
implant placement was planned. Nanocrystalline CS bone graft product graft xenograft before placing the implants in lateral incisor site. MATERIALS
(NanoGen, Orthogen, LLC, Springfield, NJ) was grafted. ePTFE barrier was used AND METHODS: A 33 year old female patient with no systemic disorder and
to close the defect. Barrier was removed after 3 weeks. The site was allowed with a partially edentulous site a horizontal ridge augmentation procedure with
to heal for 4 moths at which point, a core of the bone from the center of the a titanium- reinforced expanded polytetrafluoroethylene membrane was
grafted site was taken and implant was placed. Core was sent for histological perfomed in the left lateral incisor left before the placement of the implant and
and histomorphometrical analysis. Results: At the time of removal of ePTFE 5 months later a second surgery was realized to remove the membrane and
barrier, soft tissue was seen to be healing well. After 4 months, robust bone place the implant in this procedure using a full thickness flap and placed 1
formation was seen on the gross observation. Core of the bone was dehydrated, implant Nobel biocare with 3.5 mm of diameter and 10 mm of length and in
the same procedure we placed an implant in the right lateral incisor site with
128 the same dimensions. Prior to completion of the surgical procedure the
mucoperiosteal flap is repositioned precisely in the area of the future papillae
to make sure that wound closure is precise and tension- free RESULTS: After 5
months of there was a horizontal augmentation of 3mm thick facial bone wall
to achieve sufficient and long-lasting bone support for the facial soft tissues.
Following a healing period of 6 and 12 weeks, a reopening procedure is
recommended to initiate the restorative phase of therapy. The ridge
augmentation procedure with a titanium- reinforced expanded
polytetrafluoroethylene membrane is a predicable procedure achievement of
a harmonious gingival margin without abrupt changes in tissue height,
maintaining intact papillae, and obtaining or preserving a convex contour of
the alveolar crest.

Poster Presentation Abstracts

P229 P230

Planning Of Prosthetic Implant Mandibular Rehabilitation using Early Restoration of a Large Cystic Defect with a Combination of a Novel
Loading Protocol. Calcium Phosphosilicate Alloplast Putty and Platelet Rich Fibrin
Membrane: A Case Report.
L. Bustos*, A. Osorio México, Mexico.
G. Kotsakis*, V. Chrepa, A. Gonshor Athens, Greece.
Introduction Oral approaches describe mandibular implant overdentures
that were functionally loaded no earlier than 48 hours after implant placement Background: The most frequent odontogenic cyst is the radicular or
and no later than 3 months afterward. The use of an early load is to reduce the periapical cyst. Enucleation is the treatment of choice for radicular cysts that
treatment time. In this report case we present the planification treatment with do not interfere with anatomical landmarks. Though large mandibular cysts
the placement of implants in a female patient with 60 years old with severe exhibit spontaneous bone regeneration, the rate of bone in-growth is not
combination syndrome severe bone resorption in the posterior zone, after an adequate for a near-term implant placement. The case presented evaluates
evaluation we decided to make placement of 4 postextraction implants in the bone regeneration of a calcium phosphosilicate putty (NovaBone Dental Putty,
mandibular anterior zone and the insertion of an overdenture with a Hader NovaBone Products, Alachua, FL) (CPS Putty) when used to restore a large cystic
bar to splint the implants with early load. Materials y methods: As a first stage, defect in conjunction with platelet rich fibrin (PRF). Materials and Methods: The
a wax up of a total transitional denture using lingualized occlusal scheme with patient, a 55-year old patient presented with dull pain and tooth mobility in
physiodens tooth to satisfy the patient’s expectations. For the surgical planning, the mandibular right premolar area. Clinical examination of the area revealed
a stereolitographic model was used to prepare two surgical guides. The anterior attachment loss of 13mm & 10mm on the buccal and 11mm & 10mm on the
mandibular teeth were extracted and the first surgical guide was a screwed to lingual side of the right canine and first premolar respectively (Photo 1). Grade
obtain a flattened ridge with the necesary width to allow the placement of the 3 mobility was also recorded for the affected teeth. Pre-op Cone Beam CT
implants. The second guide was used, to define the precise implant positioning (CBCT) revealed a large radiolucency in the apical area of the involved tooth
and placement of four implants following the Straumann surgical procedure. indicative of a periapical cyst. The teeth were extracted and the large defect
A transoperative impression was taken to prepare a master model. Using the was restored with CPS putty and covered with a PRF membrane that was
master model, a Hader bar was designed using castable abutments taking the created from patients serum. The area was evaluated at 3, 5, and 7 months post-
denture setup as a reference. Two days later the bar wax-up was tested to verify operatively. Results: The healing proceeded uneventfully and the ridge width
the passiveness and tried on the cast analog model. Finally the bar processed and height remained stabled during the evaluation period. Seven month CBCT
and the denture is finished. Results: The bar is screwed to the implants and is showed good bone regeneration in the defect area. The buccal plate was
torqued to 35 newtons before losing the primary stability offered in the first two completely regenerated while the crestal plate was still remodeling. The ridge
weeks. The implants are placed without rotational forces. The denture is placed was adequate enough to place a 4.3mm x 11mm implant. The results indicate
with using tissue conditioner. .Conclusions: Even though this treatment is difficult that CPS Putty in combination with PRF membrane is a good choice to restore
to perform at the laboratory, it offers several advantages like stability and large cystic defects.
retention which provides the patient short term intial confort without affecting
the implants osseointegration

129

Poster Presentation Abstracts

P231 P235

Abutment for Occlusal Rim to Take Bite Registration without Occlusal A Novel Device to Separate Sealed Abutment from Implant in Provisional
Screw Access Hole. and Permanent Implant Restorations.
H. Tamaki*, H. Yasumufi, J. Her, S. Cho New York, NY.
M. Mitsias*, A. Vidyadharan, Y. Hanawa, S. Cho New York, NY.
In most of clinical cases, one or two temporary abutments or impression
copings were used to stabilize occlusal rim which will be used to measure Currently one of trends in implant restoration is screw and cement retained
vertical dimension and bite registration. However, screw hole openings often prosthesis (SCRP). This technique applying engaged abutment to implant and
become clogged with bite registration paste, which makes it difficult to remove superstructure was fabricated with screw access hole in occlusally and
occlusal rim, and lengthens the bite registration procedure altogether. Therefore, cemented to the crown. This allows easy maintenance when screw was
it is necessary to introduce an abutment for occlusal rim that can access without loosened or cement was wash-out. One drawback of this technique is that it
screw holes occlusaly. The purpose of this case series is to demonstrate an makes it difficult to remove bound abutment from the implant, especially if
efficient and innovative abutment without an occlusal screw hole for occlusal there is an internal conical sealed connection. The purpose of this case series
rim. Clinical indication, advantages, and limitations of this technique will be is to demonstrate various clinical usage of a device to separate sealed abutment
discussed. from implant in provisional and permanent implant restorations.

P232 P236

Clinical Indications and Advantages of Double Sided Screw Drivers for Resonance Frequency Analysis (RFA) of Three Maxillary Sinus
Implant Dentistry. Augmentation Techniques.
Y. Hemmi*, W. Yun, J. Tsutsui, S. Cho New York, NY.
P.D. Shiffler*, T. Aghaloo, J. Pi-Anfrus, P. Moy Los Angeles, CA.
Performing a treatment can involve multiple implant systems or different
sized screws. It can be frustrating if the screw driver is not compatible in the Contemporary techniques for sinus augmentation include both: 1.)
middle of procedure. This double sided driver is a versatile tool that can be used osteotome sinus floor elevation (OSFE), and 2.) the lateral window technique
with multiple screws (1.20 mm in diameter,1.27 mm in diameter or 0.9 mm, 1.2 (LWT). This study seeks to compare implant stability through reasonance
mm diameter, etc…). With this screw driver, the frustration of finding different frequency analysis (RFA) in patients who underwent osteotome sinus floor
compatible drivers is reduced. The purpose of this case series presentation is to elevation (OSFE) or sinus elevation through an immediate or delayed technique
demonstrate the efficiency of the double sided screw driver during surgical and with or without a bone graft. Data from 60 patients who underwent single stage
restorative procedures. or 2-stage implant therapy was retrospectively collected from the UCLA School
of Dentistry Implant Center from 2008-2011. Implant stability quotient (ISQ)
P233 values were collected at stage-1 and at a 3-month follow-up for single-stage
implants and at stage-1 and -2 for 2-stage implant therapy. Data was collected
Various Techniques to Remove Fractured Abutment Screws. from 20 patients in to 3 groups with patients who underwent 3 different sinus
S. Villareal*, J. Machida,, S. Cho New York, NY. augmentation techniques. ISQ values of 127 implants were then compared
between the three groups. Osteotome sinus floor elevation (OSFE) showed
One of most frustrating and time consuming experience is screw fracturing an average ISQ value of 69.448 at stage-1 and 75.181 at stage-2/follow-up with
in implant dentistry. Visibility is greatly reduced if fracturing occurs at posterior a percentage increase of 7.626% in value. Sinus floor elevation via the lateral
implant sites. Also great attention needs to be paid to avoid damaging the window technique (LWT) with immediate implant placement showed an
implant structure during the removal of fractured screw. So far there are several average ISQ value of 67.964 at stage-1 and 77.678 at stage-2/follow-up with a
different removal kits are available commercially. It is necessary to understand percentage increase of 12.505% in value. Sinus floor elevation via the lateral
how to use and when to use these kits. The purpose of this presentation is to window technique (LWT) with delayed implant placement showed an average
demonstrate the usage of various fractured screw removal kits and their ISQ value of 69.448 at stage-1 and 75.181 at stage-2/follow-up. All 3 methods
indications, contraindications and limitations will be discussed. provide for implant stability based on ISQ values. The lateral window technique
with delayed implant placement provided for the most stability according to
P234 RFA, however, does not show as large of increase in ISQ value between Stage-
1 and Stage-2/follow-up. The lateral window technique with immediate implant
Clinical Usage of Modified Bone Tacks to Enhance Stabilization of Barrier placement provided for the greatest percentage increase in ISQ value between
Membrane and Bone Substitute Material. stage-1 and stage-2/follow-up however, stage-1 ISQ values were lower than
J. Lee*, M. Lin, Y. Takashima, S. Cho New York, NY. that of the LWT-delayed group. Osteotome sinus floor elevation (OSFE) provided
the least percentage increase in ISQ values between stage-1 and stage-2 which
Bone tack was used an essential element to stabilize barrier membranes may be due to the large proportion of patients who underwent sinus elevation
during GBR (Guided Bone Regeneration) procedure to treat atrophic ridge. Thus via the lateral window technique (LWT) also received a bone graft as whereas
hermetic sealing prevent penetration of fast growing non-osteogenic cells from the OSFE group did not.
outside and allow slow growing osteogenic cells to populate. It is necessary
to place multiple tacks to achieve these goals. Too many tacks will compromise P237
blood supply and can be a source of discomfort to the patient due to exposure
or loosening. Therefore it was necessary to introduce improved tack system GBR with Tenting Screw Technology for Implant Site Development and
that will allow broader area to stabilize then the number of the necessary tacks Guided Implant Insertion: A Sophisticated Approach for Full Mouth
will be minimized. The purpose this presentation is to demonstrate clinical Rehabilitation.
advantages and indications of enhanced tack design.
M.E. Sayed*, E. Chasioti Rahway, NJ.

Various surgical procedures can be used to augment resorbed alveolar
ridges after tooth extraction. The goal is to develop techniques which are
atraumatic and less time consuming. Proper ridge width and height for eventual
optimal implant positioning can be achieved using Tenting Screw Technology
in combination with particulate allograft and resorbable collagen membranes.
Using a “staged approach”, the patient can be functional, comfortable and
maintain or improve esthetics by use of a tooth supported fixed provisional.
The interim fixed prosthesis approach avoids an interim removable prosthesis,
avoids loading of the grafted site, and gives the dentist time to assess the
patient’s oral hygiene capabilities. Immediate implant placement in the locations
of preserved natural teeth and delayed placement in previously grafted sites,
followed by immediate loading of full maxillary and mandibular arches, can be

130

Poster Presentation Abstracts

achieved with a combination of computer assisted surgical planning and guided
Implant Insertion. Success requires a team approach between the surgeon, the
restorative dentist, the laboratory and the patient.

P238

An Anatomical Study of the Maxillary Sinus and Dental Arch using ZAC
Point on CT Images
T. Watanabe*, D. Yamauchi, T. Takahashi, K. Kawaguchi.

ZAC point (intersection between zygomatico–alveolar crest and the anterior
margin of infratemporal fossa) is clinically important as a landmark for implant
surgery with sinus lift procedure. In this study, morphological measurement
of dental arch and maxillary sinus using the ZAC point were performed on CBCT
images of implant patients. A total of 50 patients participated in the study:
15 male and 35 female, with an average age of 56, ranging from 31 to 71 in
years. Their bilateral maxillary sinuses were the subject of this investigation. The
CT scanner used was a Prevista (Japan Medical Material Ltd., Japan). CBCT
DICOM data obtained this way were fed into a computer subsequently to be
turned into MPR images by SimPlant Pro 11® (Materialise Dental Ltd., Belgium).
Images so obtained were then adjusted in relation to the occlusal plane
perpendicular to the plane composed of incisive foramen and hamular notch
(pterigoid notch). Then morpho-anatomical measurements were taken of each
dental arch and the maxillary sinus in reference to ZAC point defined as above.
Average distance from ZAC point to occlusal plane was 29.4±3.4 mm in height;
average distance from theline connecting bilateral ZAC point’s to maxillary
inciser 33.0±2.6 mm anterio-posteriorlly; average distance from inter-ZAC point
line to intercuspid line 23.8±2.4 mm anterio-posteriorlly; and average distance
from inter-ZAC point line tomedial palatal cusp of first molar was 3.3±0.3 mm
anterio-posteriorlly. Additionally, average intercuspid distance was56.6±3.6 mm
horizontally, while average distance from between mesial palatal cusps of
bilateral first molars was38.4±2.6 mm horizontally.Reference points adopted in
this study are as follows: ZAC point, incisive foramen, and pterigoid notch.Values
obtained this way were fed into a commercially available version of CT implant
simulation software in an attempt to devise an optimal tooth arrangement
for the subject. Although there was an imbalance between male and female
sample sizes in this study, it is probably reasonable to assume that a denture
tooth arrangement is possible on CT implant simulation software images based
on certain anatomical information.

131

Oral Research Abstracts

OS-1 OS-3

Strain Development of Implant-supported Fixed Dental Prostheses Copy Evaluation of Implant Surface Integrity after Placement.
Milled from Zirconia Ceramic. D.O. Mints*, C.N. Elias, P. Funkenbusch, L. Meirelles Rochester, NY.

M. Karl*, G. Schmidtler Erlangen, Germany. The surfaces of modern dental implants have been modified to enhance
osseointegration. This study aims to examine the surface integrity associated
Introduction Passivity of superstructure fit is still considered a prerequisite with implant placement, to determine whether the surface topography of
for successful implant therapy. The aim of this investigation was to quantify the common modifications is retained after implantation. Turned (T), acid-etched
strain development of cement-retained three-unit implant-supported fixed (AE) and anodized (Ano) implants were prepared. Implants with identical design
dental prostheses (FDP) copy milled from zirconia ceramic. Methods Based were inserted into Grade 30 polyurethane blocks (Sawbones, WA-USA), which
on an in vitro model situation with two implants in the lower left quadrant, is used to approximate Type 3 & 4 bone, using routine drilling protocol at max.
three groups (n=10) of restorations were fabricated following conventional torque of 37 N*cm. Qualitative analysis of the apical region and implant threads
impression making and master cast fabrication. Standardized three-unit cement- of predrilled and postdrilled implants was done by scanning electron
retained FDP frames were manufactured by means of casting (high noble alloy), microscope (SEM, Zeiss Auriga, Oberkochen-GER) and quantitative analysis of
copy-milling (presintered zirconia ceramic) and CAD/CAM (presintered zirconia the implant threads was performed by interferometer (Zygo 7100, CT-USA)
ceramic). During cementation of the restorations on the in vitro model, the using a 20x lens with a scan area of 210x70 µm. Among some of the roughness
emerging strains were recorded using strain gauges attached on the model parameters calculated were: average height deviation (Sa), peak height above
material mesially and distally adjacent to the implants. The absolute strain values core roughness (Spk) and maximum peak height (Sp). SEM images at different
served as basis for statistical analysis applying multivariate analysis of variance magnifications demonstrated damage caused by the drilling procedure on all
(MANOVA) with Pillai’s trace. The level of significance was set at α = 0.05. Results three implant types. Grooves on the T implants at the apical region were visibly
The mean absolute strain development at the different strain gauge positions worn down and in some cases completely removed. AE implants had a few
ranged from 85.39µm/m to 326.83µm/m. MANOVA revealed a significant localized flattened areas on the tops of threads, which correspond with the
influence of the factor fabrication method on strain development (p = 0.011) direction of insertion. Ano implants showed the most extensive damage on the
with the cast restorations showing the highest strain development and the surface. Mostly concentrated on the apical region, entire layers of thick oxide
CAD/CAM fabricated FDPs showing the lowest. Subsequent tests of between were stripped away. Surface topography evaluation of postdrilled T/AE implants
subject effects revealed significant differences in strain development for the showed similar Sp/Spk/Sa values compared to the original. Ano implants were
different FDP types at all strain gauge locations with the exception of the strain more complex to measure quantitatively, due to variation in the extent of
gauge positioned mesially to the anterior implant (p = 0.267). Conclusion Copy damage to the oxide layer during insertion: (a) completely removed exposing
milling of implant-supported FDP frames may lead to restorations which are the underlying material and (b) intact. Conclusion: Lack of surface integrity was
more precise than cast restorations but less precise than CAD/CAM fabricated found in the apical region of all three groups and Ano implants showed damage
restorations. Investigating FDP frames may be seen as a limitation of this study, on the threads. The current results indicate some material loss after insertion,
as ceramic veneering of may further contribute to the total strain development however it is unclear whether the amount of loss is sufficient to affect bone
of an implant-supported restoration. formation and long-term success of the implant rehabilitation.

OS-2 Roughness Parameters Before and After Insertion

Preservation of Crestal Bone by Implant Design: A Comparative Study OS-4
in Minipigs.
A Comparative Study of 5-axis Milling and Design-Related Processing
L.J. Heitz-Mayfield*, I. Darby, F. Heitz, S. Chen West Perth, WA, Australia. for Implant Surgical Templates.
J. Park*, T. Lee, J. Heo, J. Koak, S. Kim, S. Heo Seoul, Republic of Korea.
Implant design characteristics aimed at preservation of crestal bone include
horizontal offset of implant/abutment interface, internal abutment connections, Objectives: The aim of this study was to evaluate the accuracy of surgical
thread configuration and surface modifications. There are few comparative templates fabricated using coordinate synchronization processing with 5-axis
studies evaluating crestal bone levels at implants of different designs. Thus the milling and design-related processing utilizing Rapid Prototyping (RP) by means
aim of this experimental study was to compare crestal bone levels at 3 of reverse engineering procedure. Materials and methods: The pilot study was
commercially available bone level design implants; Straumann® Bone Level performed on five edentulous models. The synchronization of the milling
implant (SBLI), Astra® Osseospeed implant (AOI) and Nobel Biocare® Replace coordinates was performed using the conversion process for the
Tapered Groovy Implant (NBTI). Materials and methods: In 12 minipigs one ‘Synchordination Platform’ located on the bottom of the model. Drilling was
implant of each design was placed on each side of the mandible according conducted according to the planned vector and depth. An accuracy analysis
to the implant manufacturer’s recommendations. On one side implants were was performed with 3D-Doctor and Solidworks software by measuring the
placed at the level of the crest, while on the other side implants were placed vector of stopping’s top and bottom centers through merging and reverse
1 mm above the crest. Closure screws were placed to allow submerged healing. engineering of the planned and post-drilling CT image. The comparative study
At 4 weeks, 6 animals were prepared for histologic analysis. In the remaining was performed on the master model with ten embedded gutta-percha
6 animals transmucosal healing abutments were connected until 12 weeks stoppings hidden under the artificial gingiva. The RP-produced template was
when histomorphometric analyses were made. Radiographs were taken at fabricated using a stereolithography machine at the RP center. The metal sleeves
implant placement, 4 and 12 weeks. Clinical parameters were assessed at 12 were bonded after boring the holes (Group TRP). For the milled template, the
weeks. Outcome variables included histologic and radiographic bone levels. framework was constructed on the model using orthodontic resin, and metal
ANOVA and Mann-Whitney tests were performed and p-values adjusted for bushings were set on the holes milled on the 5-axis milling machine (Group
multiple comparisons. Results: At 4 weeks there were no statistically significant TM). To avoid errors due to the tolerance limit of each group, accuracy analysis
differences in histologic or radiographic bone levels between implant designs. was performed by measuring the vector of the metal bushing against that of
At 12 weeks, clinical examination showed healthy peri-implant tissues. Implants the cylinder of the master model. The repeated measures multivariate analysis
placed with the implant shoulder 1 mm above the crest had minimal bone loss of variance was performed with SPSS (α=0.05). Results: The deviation between
at 12 weeks, with no statistically significant differences between implant planned image and drilled bore that was reverse engineered was 0.31 mm
designs. When the implant shoulder was placed at the level of the crest the
SBLI and the AOI implants preserved significantly more crestal bone than the
NBTI at 12 weeks (p< 0.01). At 12 weeks the mean histologic facial bone level
in relation to the implant shoulder was -0.3 ± 0.3 mm at the SBLI, -0.1 ± 0.2 mm
at the AOI and -1.0 ± 0.3 mm at the NBTI. Mean radiographic bone levels in
relation to the implant shoulder were 0.0 ± 0.3 mm for the SBLI, -0.1 ± 0.4 mm
for the AOI, and -0.9 ± 0.8 mm for the NBTI. Conclusion: Implant design
characteristics influence crestal bone levels with greater bone preservation
observed for the SBLI and AOI compared to the NBTI.

132

Oral Research Abstracts

(range: 0.15 - 0.42 mm) at the entrance, 0.36 mm (0.24 - 0.51) at the apex, and Table 1. Element Results from ICP Detection (ppm), mean±std. dev.
angular deviation was 1.62 ° (0.54 - 2.27). There was positive correlation between
the deviation at the entrance and that at the apex (Pearson Correlation OS-6
Coefficient = 0.904, P = .013). The deviations in the RP-produced template were
significantly larger than those of the milled surgical guide (P < 0.05). The Effect of Multilayer RhBMP-2 DNA Coating on Osteoblastic
maximum deviations of the TRP group were 1.58 mm (horizontal), 1.68 mm Differentiation In Vitro.
(vertical) and 8.51° (angular), and that of the TM group were 0.68 mm Q. Jiang*, F. He, G. Yang, S. Zhao Hangzhou, China.
(horizontal), 0.41 mm (vertical), and 3.23 ° (angular). Conclusion: The accuracy
of the computer guided 5-axis milled template was within the safety margin of Objectives: This work was to investigate the influence of the multilayer
2 mm and was comparable to that of the RP-produced template. cationic liposome (Lip)/pcDNA3.1(+)-rhBMP-2 complex (LDc) coating on dual
acid and sandblasted titanium implants surface on osteoblastic proliferation
Templates fabricated by Rapid Prototyping machine (left), and 5-axis milling machine and differentiation, as well as on the gene expression of differentiation markers
(right) in MC3T3-E1 cells. Materials and methods: The multilayered structures
composed of hyaluronic acid (HA) and LDc were fabricated on titanium implants
OS-5 by layer-by-layer (LbL) assembly technique. MC3T3-E1 cells were cultured on
HA/LDc LbL-modified surface, titaniuim surface without coating were set as
Galvanic Corrosion of a Combination Porous Tantalum and Titanium control. The rhBMP-2 protein secreted into supernate and the proliferation and
Alloy Implant. differentiation behaviors of MC3T3-E1 cells were investigated. Gene expression
J. Lee*, M. Collins, H.B. Wen, S. Papanicolaou, A. Deardorff, D. Harney of OC, ALP, Runx2 and Osx were also detected. Results: The results demonstrated
Carlsbad, CA. that rhBMP-2 protein secreted into culture medium was significantly higher
than control groups. RhBMP-2 levels in HA/LDc coating group peaked at day
Introduction: Tantalum (Ta) and titanium alloy (Ti-6Al-4V) are highly 3 to about 0.75 ng/ml of rhBMP-2, and declined to undetectable levels by 15
biocompatible materials with stable surface oxide layers that help resist days of culture. Control group cells showed almost no detectable rhBMP-2-
corrosion. However, combining dissimilar metals may heighten the risk of release into the medium at any time point. MC3T3-E1 cultured on HA/LDc
galvanic reaction, ion release, weakening of the restoration and adverse clinical coating displayed significantly higher production levels of alkaline phosphatase
responses. The purpose of this study was to evaluate galvanic corrosion in vitro (ALP) and OC over 7 days and 14 days culture, respectively. At 7 days, the ALP
on a combination Ta and Ti-6Al-4V implant after 6 months of immersion testing. activity in the HA/LDc group (0.78 ± 0.13 nmol/ug/hr) was almost twice that
Methods: The test implant consisted of cervical, apical and central core sections of cultures on control group (0.41 ± 0.1 nmol/ug/hr) (P=0.001). At 14 days,
of Ti-6Al-4V, and a porous Ta midsection. A total of 60 implants (4.1mmx13mm) this significant difference remained HA/LDc group (0.92 ± 0.12 nmol/ug/hr),
were placed into 2 containers of Ringer’s solution maintained at 37°C. After 6 as compared with control group (0.68 ± 0.17 nmol/ug/hr)(P =0.018). MC3T3-E1
months, the amount of Ti-6Al-4V and Ta in the 2 test solutions was quantified cells of the HA/LDc group exhibited upregulated gene expression of the
by inductively coupled plasma (ICP) analysis. Results: Test solutions were differentiation markers, especially on days 12 for OC and on days 6 and 12 for
compared with fresh, unused Ringer’s solution (2 test solutions vs. 1 control ALP (Fig.1). Conclusion: In conclusion, The multilayer HA/LDc coating was
solution). Visual analysis of each implant was also conducted with a beneficial to the proliferation and differentiation of MC3T3-E1 cells on dual acid
stereomicroscope (magnification=20x). There was no observed material loss and sandblasted titanium implant.
through surface pitting or evidence of morphology changes associated with
galvanic corrosion. Chemical analysis of the Ringer’s solutions after the 6-month Fig.6 Quantitative PCR analyses of MC3T3-E1 cells at various time points. Relative
test showed no significant statistical differences among test and control amounts of mRNA for Runx2, ALP, OC, Osx were quantified by real-time RT-PCR and β-actin
solutions (Table 1). The combination of Ta and Ti-6Al-4V in the porous dental was used as internal control. *Statistically significant difference (P < 0.05) between
implant assembly did not show evidence of galvanic corrosion based on visual experimental and control groups at the given time point. The data shown are the mean
and chemical analysis techniques. Conclusion: The combination Ta and Ti-6Al- levels of relative gene expression ± S.E. from three independent experiments, analyzed
4V did not create a risk of galvanic corrosion, which is clinically significant when in triplicate .
these metals are combined in a dental implant design.

133

Oral Research Abstracts

OS-7 OS-9 – WITHDRAWN

Effect of Long-term Bisphosphonate Therapy on Oral Wound Healing. Fluorescence Microscopic Analysis of Bone Osseointegration of
Magnesium and Strontium Substituted Nanohydroxyapatite Implants.
J. Yamashita*, S. Kuroshima Ann Arbor, MI.
J. Zhao*, L. Liu, Y. Fan, D. Fu, S. Ying Hangzhou, China.
Osteonecrosis of the jaw (ONJ) is an emerging condition associated with
the use of antiresorptives for metastatic bone diseases and the management Objectives: the purpose of this study was to evaluate the effect of Strontium-
of osteoporosis. More than 30 million Americans are being treated with
antiresorptives currently and this figure is continually increasing as the substituted hydroxyapatite and Magnesium-substituted hydroxyapatite on the
population ages. Accordingly, the prevalence of ONJ could rise considerably in
the near future and its increasing impact on public health including implant bone osseointegration of the implant using fluorescence microscopy analysis.
dentistry requires attention. However, the pathophysiology of ONJ is unknown.
We previously reported at an AO annual meeting that long-term Materials and methods: A total of 15 implants were placed into the distal femoral
bisphosphonate therapy has no influence on the bone-to-implant contact of
implants placed in rat tibiae. In the current study we investigated the effect condyle of 8 New Zealand white rabbits. Implants were seperated into 3 groups:
of long-term bisphosphonate therapy on oral mucosal wound healing using
a mouse model. Zoledronic acid was administered to adult mice for 13 months. pure hydroxyapatite (HA), Strontium-substituted hydroxyapatite (Sr-HA)and
To evaluate mucosal wound healing, a portion of the palatal mucosa was
excised to expose the bone 3 weeks before euthanasia. The therapeutic effect Magnesium-substituted hydroxyapatite (Mg-HA), each group contained 5
of bisphosphonates on the skeleton was assessed by the microCT scanning and
histomorphometric analysis of the femurs. Serum levels of TRAcP5b and calcium implants. During the healing period polychromatic fluorescence labelling was
were analyzed for osteoclastic bone resorption and calcium homeostasis.
Histomorphometric analysis of the oral wound healing was performed in TRAP- performed with three different fluorescent dyes. Oxytetracycline hydrochloride,
, H&E-, Trichrome-, and Brown&Brenn-stained sections. Bisphosphonate therapy
for 13 months significantly suppressed bone resorption resulting in higher bone Alizarin-complexon and Calcein green were administered 7, 28, 46 and 53 days
mass compared to control. However, a serum osteoclast marker, TRAcP5b, was
not suppressed by bisphosphonate therapy. Although gross healing of oral ppaferteerpfroatrhrmeedeimdfoptrolafnalutsasoteriosesnsc,foerernsctpheeecmtpWivirceerIlsoyTe.snAcHcofteDpeyorR8fasAwnigaeWnleyiksfNsiicsta.hnOetnfedemi-fwfuearrseywnAceeNresOrbVeeAttriweteveesetdn and
wounds was normal, histomorphometric analyses revealed significantly was
impaired healing in the bisphosphonate-treated group. Such an impaired the
healing was characterized by significantly more PMN infiltration and less
collagen fiber deposition than control. Interestingly, no differences were noted results. Results: The bone mineral apposition rates for all implants were calculated
in the osteoclast perimeter (#/mm) between groups but the bisphosphonate-
treated group exhibited significantly increased numbers of TRAP+ giant cells during 7th day and 53th day after implantation. For Mg-HA implants, the bone
in oral wounds. No gram positive and negative bacterial invasions into wounds
were observed. The results of this study show that long-term bisphosphonate mineral apposition rates (2.137 ± 0.435 µm/day) were greater than that for pure
therapy stimulates giant cell formation in oral wounds, thereby impairing
wound healing of oral mucosa. HA (1.779 ± 0.435 µm/day) from 7 and 28 day time periods but not significantly

OS-8 (p=0.185). For the Sr-HA group, the bone mineral apposition rates (1.835 ±

A Comparison of Fracture Resistance and Damage Modes of the Implant- 0.317µm/day) were not significantly greater than that for pure HA (1.779 ± 0.435
abutment Interface between Titanium Alloy and Zirconia Abutments.
µm/day) from 7 and 28 day time periods (p=0.456). At 7th day, the Mg-HA coated
L. Fuh*, C. Wang, Y. Shen, J. Hsu, H. Huang Taichung, Taiwan.
group had significantly higher BIC all along the length compared with HA group
Even though zirconia has been accepted as an esthetic material for
restoration, there are still functioning concerns for the mechanical properties (p=0.018). At 53th day, significant differences were remained between two
to withstand forces in the oral cavity. The purpose of this study was to compare
the fracture strength and failure mode of titanium alloy and zirconia abutments groups (p=0.032). For the Sr-HA group, the BIC over the total length showed
under oblique compressive forces with relatively different implant-abutment
levels. Materials and Methods: Twenty-four 4 X 13 mm simulated MK III implants no significantly differences compared with pure HA at all time points. And Mg-
(Nobel Biocare AB) were used in the study. Implant-abutment assemblies were
set up following the modified ISO 14801 specifications. These implants were HA coated group had significantly higher BIC all along the length compared
divided into two groups: group A (simulating bone loss of 3.0 mm) and group
B (simulating bone loss of 1.5 mm). Both groups A and B were then divided into with Sr-HA group at 7th day (p=0.022), but had no significant differences at 53th
two subgroups of six implants each (subgroup 1 were connected with titanium
alloy abutments, subgroup 2 were connected with zirconia abutments). Each day. Conclusion: the Mg-HA can improve the bone osseointegration of the
implant- abutment interface was observed with a scanning electron microscope
(JEOL, JSM 5400, Japan) both before and after testing. A 30 degree oblique implant on the early stage. However, more experimental trials have to be carried
force was then applied to a custom designed hemispherical stainless steel
cap until failure using a universal testing machine (AG-IC, Shimadzu, Japan) out on higher mammals that show a metabolic rate of bone that is more
with a cross head speed of 1.0 mm/min. The maximum deformation force and
fracture force of each sample was then recorded. The data were analyzed with comparable to humans.
the nonparametric test (Mann–Whitney). Results: From the SEM, level of damage
was found in the order of group B2 > group B1 > group A2 > group A1. The OS-10
mean maximum deformation force and fracture force obtained respectively
were A1: 548.7 N, 734.5 N; A2: 550.7 N, 908.5 N; B1: 1114.2 N, 1292.1N; B2: 998.3 3D Evaluation of Osseointegration of ZrO Implants: A Comparison with
N, 1220.7 N. For maximum deformation force, significant difference was noted Histomorphometry.
between subgroup B1 and B2 (P= 0.01), but no significant difference between
subgroup A1 and A2. Fracture forces were no different between subgroup A1 S. Vandeweghe*, R. Jimbo, A. Wennerberg Gent, Belgium.
vs. A2 and B1 vs. B2. Conclusion: Based on the experimental results, the more
marginal bone support was lost, the less maximum deformation force and Introduction: Although histology has proven to be a reliable method to
fracture force were obtained, but all tested implant-abutment assemblies could evaluate the ossoeintegration of a dental implant, it is expensive, time
withstand physiological occlusal forces applied in the anterior region. Less peri- consuming, destructive and limited to 1 or few sections. Micro-ct is fast and
implant bone loss, choice of abutment materials would affect the obtained delivers 3D information, but this technique has not been widely used and
maximum deformation force validated yet. Therefore, the aim of this study was to compare micro-ct and
histomorphometry. Materials and methods Sixteen polished non-threaded ZrO
implants of 9.0 mm length and 4.2 mm diameter were placed in 8 lop-eared
rabbits. After 2 and 4 weeks, the rabbits were sacrificed with an overdose (60
mg/mL) and the samples were retrieved. The 3D bone formations around the
implants were examined using micro computed tomography with a slice
resolution of 36 µm. Five hundred µCT slices were imaged at an X-ray energy
level of 55 kVp, and a current of 145 µA. The acquired data were further analyzed
and quantified using Amira software(Visage Imaging GmbH, Berlin, Germany).
After the µCT analysis, all samples were processed for undecalcified ground
sectioning. The sections were ground to a final thickness of about 40 µm and
stained with toluidine blue. Histological evaluations were performed using a
light microscope and histomorphometrical data were analyzed by an image
analysis software (Image J ver.1.43u; National Institutes of Health). Bone-Implant
contact (BIC) percentage and Bone Area (BA) percentage were calculated using
both techniques. Results In total 16 ZrO implants were installed. All implants
healed uneventful. The mean BIC was 28.49% and 42.51% after respectively 2
and 4 weeks when measured by histomorphometry, while it was 33.74% and
42.19% when measured with µCT. BA was 30.59% and 47.17% after 2 and 4
weeks for histomorphometry and 37.16% and 44.95% for µCT. Correlation
between histomorphometry and µCT was significant for both, BIC (0.619,
P=0.011) and BA (0.787, P<0.001). Only the 2 weeks BA for the titanium implants
was significantly different between µCT and histology (P=0.008). Conclusion
Although the technique has its limitations, micro-ct corresponded well with
histomorphometry and can therefore be a valuable tool to examine bone
structures around implants.

134

Oral Research Abstracts

3D representation of the implant with the surrounding bone

OS-11 OS-12

Bone Repair using Variable Mesopore 3D Printed Tricalcium Phosphate The Effect of Electrical Stimulation on Healing of Bone Grafts: A Pilot
Scaffolds. Study.

J.W. Goetz*, E.A. Clark, S.R. Iyer, J.L. Ricci New York, NY. G. Talwar*, C.F. Driscoll, R. Masri Baltimore, MD.

Introduction: Current bone grafts are imperfect and not designed for a Purpose: Bone grafting is an important step for reconstruction of the
specific site. 3D printed, Direct Write (DW), scaffolds composed of complex masticatory system. Bone grafting is unpredictable and is associated with lower
multicomponent biphasic (COMBI) calcium phosphate can be custom-fabricated success rate, extended healing times and morbidity. Methods that expedite
to repair bone defects. Current literature debates optimum and threshold pore healing and increase predictability will contribute to the overall success of
sizes for bone repair. The objective is to examine the relationship between reconstructive efforts. In this project, the effect of electrical stimulation on bone
scaffold pore size and bone density, ingrowth, and bone scaffold remodeling graft healing in rat calvaria was examined. Materials and Methods: Fifteen adult
in a critical-sized defect. Methods: Mesopores (spaces defined by strut borders) male Sprague-Dawley rats were used. A 7 mm diameter bone defect was
varied in the x, y, and z planes. Two 11mm dia. disk scaffold designs of layers created at the midline. The site was grafted using freeze dried mineralized bone
of nested concentric circles, alternating with radial struts of 1, 2, or 3 stacked and bipolar platinum stimulating electrodes were overlaid on the center of the
layers in height, were DW printed of 15:85 HAP/β-TCP ink sintered at 1100°C. graft. A loop in the electrodes was sutured to the overlying skin. Animals were
Radial struts around a disk result in a series of pizza-slice-like wedges where divided into two groups. The experimental group had 8 animals and received
the mesopore size decreases in a controlled linear series from 940µm at the electrical stimulation (3 times/day for 10 days) and the control group consisted
outer edge to 100µm at the inner portion of the wedge at the disk center. of 7 animals and received no stimulation. At 6 weeks, the grafted areas together
Scaffolds were placed in rabbit bilateral trephine defects. After 8-16 weeks, bone with the surrounding bone were harvested. Tissue sections were prepared and
ingrowth and scaffold/bone remodeling were quantified by MicroCT and hard stained using hematoxylin-eosin. For each animal, the grafted area was marked
tissue histology. Results and Conclusions: Bone volume was higher in the more and the percent of new bone, remaining graft material and connective tissue
open, less scaffold-strut dense areas. Bone grew into all varied height layers. was calculated. Results: In the experimental group, full 10 day electrical
Pores larger than 500µm still filled with bone well, contrary to previous literature stimulation was carried out in 5 animals. The remaining animals (n=3) were not
findings. At 8 weeks, as mesopore size decreased, bone volume decreased from included because in two animals the electrodes broke after 3 and 6 days of
40% to 9% of total volume. Scaffold remodeling decreased from 13% to 5%, stimulation and in one animal the sections were lost during specimen
and was largely proportional to bone density. At 16 weeks, as mesopore size preparation for staining. ANOVA revealed that there was statistically significant
decreased, bone volume decreased from 56% to 10%. Scaffold remodeling differences between the two groups. Post hoc analysis revealed that the animals
decreased from 23% to about 5%, and was also largely proportional to bone that received electrical stimulation had more new bone (3.81 (3.6) %; p=0.034)
density. Variable porosity scaffolds showed that bone could be conducted into compared to the control group (0.47 (0.52) %). The amount of remaining graft
mesopores as large as 940µm (although bone appears to take longer to material was significantly higher in the control group (26.11 (6.54) %; p=0.024)
penetrate these pores), and into mesopores as small as 100µm. Larger pore compared to the stimulation group (16.64 (5.28) %;). No significant difference
sizes allowed more bone ingrowth, and amounts increased over time. Scaffold (p=0.15) was found between the 2 groups in the amount of connective tissue
remodeling was directly related to amounts of bone and time: more bone (stim. Group: 79 (5.47)%; control group: 73.2 (6.82) %). Conclusion: In this animal
resulted in more remodeling over time. This study demonstrates the properties model of bone graft healing, electrical stimulation produced significantly more
of unique variable porosity that will allow custom fabrication of bone repair bone formation and less remaining graft material. These findings suggest that
scaffolds with controlled densities, mechanical properties, bone fill electrical stimulation expedites bone graft healing.
characteristics, and remodeling rates.

135

Oral Research Abstracts

OC-1 they ingested placebo. For all patients, a steroidal anti-inflammatory (8mg
dexamethasone) was administered 1 hour preoperatively, and 0.12%
A Clinical Study Correlating Implant Stability by Resonance Frequency chlorhexidine mouthwash was prescribed three times a day postoperatively for
Analysis at Implant Level with Abutment Level. 10 days. Patients in whom it did not achieve 32Ncm initial implant anchorage
were excluded and replaced with the same random number. Clinical evaluation
R.K. Han*, P.A. Schnitman Boston, MA. was performed 1, 2, and 4 weeks after implant installation, to register any signs
or symptoms of infection; and after 3 months, at the time of prosthesis
Background and purpose: Three primary implant placement protocols have installation, regarding implant survival and marginal bone loss. The results
evolved: 1) submerge Ç wait 3-6 months Ç expose and restore; 2) expose, out did not reveal statistical difference for infection, marginal bone loss, or implant
of occlusion Ç wait 3-6 months Ç restore; 3) load in function at placement. survival (Two-Way Anova p > 0.05) between groups. The patients included in
All three protocols can deliver a successful outcome, depending on initial this sample did not benefit from the use of systemic antibiotics during single-
implant stability. Previous studies have discussed how to measure implant implant surgery with immediate healing abutment installation.
stability, but there has been great controversy over which technique is accurate
and reproducible. Resonance Frequency Analysis(RFA) has shown promising OC-3
objective results in terms of Implant Stability Quotient (ISQ), at implant level
when compared to other methods such as - insertion cutting resistance, the Bone Physiology in Human Grafted and Non-grafted Extraction Sockets
percussion test, insertion torque, reverse torque, and the Periotest©. However, - An Immunohistochemical Study.
until now RFA measurements have not been available following abutment
placement, during final restoration fabrication, after delivery, and during long- S. Nahles*, C. Nack, K. Gratecap, H. Lage, J.J. Nelson, K. Nelson Berlin,
term follow-up. The aim of this study is to determine if the resonance frequency Germany.
analyzer can provide accurate and reliable measurements at both fixture level
and abutment level. Materials and methods: Nineteen implants (NobelBiocare, Purpose: The aim of the present clinical investigation was to define and
RP External hex) in three patients, which were to receive abutments for final compare the osteogenic potential and to evaluate its correlation with the
restoration, were identified. At insertion, all of the implants were immediately vascularisation of the provisional matrix in grafted and ungrafted extraction
loaded. One-year post insertion, ISQ buccal-lingual (BL) and mesio-distal (MD) sockets after 4 and 12 weeks of healing. Methods: A total of 33 Patients (15
measurements were obtained. The stability ISQ of each implant was measured female, 18 male) with 65 extraction sites with a mean age of 54.4 years (30 –
at fixture level and at abutment level, and the abutment heights were recorded. 73 years) participated in this study. After tooth extraction the sockets were
Results and discussion: Mean MD ISQ measurements at fixture and abutment augmented with Bio-Oss collagen or non-augmented. At implant placement
level was 77.67 ± 11.49 and 54.53 ± 10.16 respectively. Mean BL ISQ after four or twelve weeks bone biopsies were obtained. Within the specimens
measurements at fixture and abutment level was 78.63 ± 8.96 and 51.95 ± 10.75 the osteogenic and endothelial potential of mesenchymal cells was analyzed
respectively. Mean difference between fixture and abutment level in MD in the provisional matrix using immunohistochemical analysis with three various
direction was 23.13 ± 7.13, while mean difference between fixture and abutment monoclonal antibodies cbfa1/Runx2 and Osteocalcin (OC) and CD31. For the
level in BL direction was 26.68 ± 8.19. There was no significant difference in statistical analysis the Mann-Whitney U-test, Spearman’s rank-order correlation
measurements directionally. The ISQ measurements at abutment level were coefficient and the two-factorial analysis for repeated measurements were used.
significantly lower than at fixture level (p≤0.05). The ISQ measurements for all Results: Of 65 extraction sockets 25 (13 non-augmented, 12 augmented) sites
implants at abutment level decreased as the abutment height increased. after four weeks healing time and 40 (19 non-augmented, 21 augmented) sites
Conclusion: in this group of patients, there is a statistically significant difference after 12 weeks healing time were involved in the study. No signs of acute or
between fixture level and abutment level ISQ measurements (p≤0.05). chronic inflammation were noted in any specimens. After four weeks a median
amount of 56 % (10 – 85 %) of Cbfa1 positive cells and a median amount of
cells expressing OC was 21 % (5 – 42 %) was measured. A median CD31 score
of 5 was documented. After twelve weeks a median amount of 61 % (19 - 90
%) positive cells expressed by Cbfa1/Runx2 a median amount of OC positive
cells of 9 % (2 - 17%) was calculated. The results revealed a median score
regarding CD31 positive cells of 3. Discussion: After four weeks healing period,
the provisional matrix displayed a high osteoblastic activity. The active zone of
bone formation is found in the apical region of the extraction socket during
the early healing phase. After twelve weeks the bone remodeling is slower and
predominantly found in coronal region of the socket. So,there is a concomitant
change of vascularisation with the activity of osteoblasts.

OC-2 OC-4

Do Systemic Antibiotics Provide Better Clinical Outcomes in Single-Tooth A Prospective Study on the Accuracy of Dentally Supported
Implant with Immediate Healing Abutment Surgery? A Double-Blind, Stereolithographic Surgical Guides in Partially Edentulous Maxillae.
Prospective, Randomized Controlled Clinical Trial.
J. D’haese*, L. Elaut, H. De Bruyn Berlare, Belgium.
G.S. Pimentel*, C.E. Francischone, A.C. Montenegro, K. Temponi, G. Reis,
N. Cardozo, N.P. Leme Rio de Janeiro, Brazil. Background: Flapless implant placement using guided surgery is
widespreadly used, although clinical publications on the precision are lacking.
This prospective double-blind randomized controlled clinical trial evaluated Aim: To evaluate accuracy of dentally supported stereolithographic guides in
the use of systemic antibiotics for single-tooth implant surgery, with immediate the edentulous maxillae. Material and Methods: 36 OsseoSpeed™ implants were
installation of the healing abutment. Thirty patients were selected based on installed using dentally supported stereolithographic surgical guides
the following exclusion criteria: systemic pathologies (diabetes mellitus, consecutively in 13 patients. At least 2 implants (Osseospeed TM, Astra Tech
nephropathies, and hepatic illness), use of immunosuppressive agents (chronic AB, Mölndal, Sweden) were planned for each patient. The post-operative implant
use of steroidal anti-inflammatory agents, chemotherapy and radiotherapy), location was assessed with a CT scan. Software was used to fuse the images
local pathologies (periodontal disease, hard or soft tissue alterations). Two of the virtually planned and actually placed implants, and the locations, axes
groups of fifteen patients were arranged: Group A (control) received 1g and inter-implant distances were compared. The final prosthetic construction
amoxicillin 1 hour before surgery; Group B (test) did not receive antibiotics, was made at least 3 months after implant installation by the referring dentist.
Results: Thirteen partially edentulous adults were included in this clinical trial.
136 The population consisted of 5 males and 8 females. Mean age was 50.38 years
(range 20–81). Out of the 13 patients, 4 were current smokers (more than 10
cig/day). Total number of implants inserted was 36. One severe complication
in terms of misplacement was noticed due to a misfabrication of one of the
surgical guides. Mean coronal deviation ranged between 0,19 mm and 2,08
mm with a mean of 0,77 mm (SD 0,49 mm). Mean apical deviation ranged
between 0,21mm and 2,70 mm with a mean of 1,09 mm (SD 0,65 mm). Mean
angular deviation ranged between 0,72° and 6,75° with a mean of 2,70° (SD

Oral Research Abstracts

1,55°). No significant differences were found when comparing global coronal (p < 0.05). There were no statistically significance differences between the two
and global apical deviation for the different implant length groups and different groups (p > 0.05). The mean mid-buccal vertical change for the Cancellous
implant locations. Conclusions: This report confirms former publications in group was a gain of 0.6 ± 2.3 mm (p < 0.05) vs. a loss of 0.8 ± 0.8 mm for the
literature regarding accuracy of stereolithographic designed surgical guides. Demineralized group (p > 0.05). There were no statistically significant differences
Clinicians should be warned that substantial apical deviations could be between groups for vertical change (p > 0.05). Histologic analysis revealed that
expected when implants are inserted using stereolithograpic surgical guides. the Cancellous group had 38 ± 14% vital bone, 29 ± 14% non-vital bone, 32 ±
No significant differences were found regarding accuracy between the different 10% trabecular space, while the Demineralized group had 40 ± 13% vital bone,
implant length groups and also between smokers and non-smokers. One should 21 ± 14% non-vital bone, and 39 ± 11% trabecular space. There were no
be aware of the fact that metal restorations in the neighbouring teeth result statistically significant differences between groups for vital or nonvital bone or
in a lot of scattering. This could complicate the production process of the guide for trabecular space (p > 0.05). Conclusions. Both treatments were effective in
leading an additional risk of production errors. the preservation of horizontal and vertical ridge dimensions for future implant
placement. The Demineralized group, however, healed with a high percentage
of vital bone, despite previous reports to the contrary, and the percentage of
vital bone was similar to the amount achieved by the Cancellous group.

Clinical example illustrating the fabrication error case: a+b: the location of the implants OC-6
(yellow) deviate in a buccal direction and perforate through the buccal bony wall compared
to the planned position (red); none of the implants reach the pre-operatively planned Immediate Loading in Full Arch Rehabilitations: A Retrospective Cohort
depth Study.

H. Francisco*, A. Mata, D. Marques, M. Real Dias, A. Moreira, F. Freitas,
J.O. Caramês Lisbon, Portugal.

INTRODUCTION: Immediate implant loading is a viable treatment method
in selected cases. However, little is known regarding the amount of implants
placed in the maxilla and mandible for a successful immediate loading protocol.
OBJECTIVES: Compare implant survival using an immediate loading protocol
in patients with four implants placed in the maxilla, with patients with four
implants placed the mandible, in full arch rehabilitation. SETTING: Portuguese
private dental clinic. DESIGN: retrospective cohort. SUBJECTS: 440 implants
placed in 110 patients with immediate loading protocol. MATERIALS AND
METHODS: Participants were assigned to either one of two groups based on
the location of the immediate loading protocol: 4 implants placed in the maxilla
(Group 1) and 4 implants in the mandible (Group 2). Smoking status, gender,
periodontal disease, smoking and diabetes were recorded and considered as
covariates. Follow up periods ranged from 3 to 72 months with appointments
at 6 months intervals. Survival analysis with Cox regression model, Kaplan-Meier
and Long Rank test were used as appropriated. Confidence level was set at 95%.
Alpha was set at 0,05. MAIN OUTCOME MEASURES: Implant cumulative survival,
Risk for implant loss. RESULTS: Significant differences (p<0,05) were found for
cumulative implant survival comparing both groups up to 24 months of follow
up: 73% for the maxilla and 97% for the mandible (Log Rank test significant).
Cox regression model suggested that only the covariate gender was significantly
different with increased loss for implants placed in male patients. Men have
three times higher chance of implant loss in the maxilla. CONCLUSIONS: The
results suggest that there are differences in implant survival for immediate
loading with four implants in the maxilla, when compared with four implants
in the mandible. Moreover, the risk for implant failure was increased in male
patients when compared with female patients. Diabetes, smoking status and
periodontal disease did not affect any of the results.

OC-5 OC-7

Ridge Preservation Comparing Demineralized Particulate Allograft and A Randomized, Controlled, Multicenter Study Comparing Short Implants
Mineralized Cancellous Allograft using a PTFE Barrier: A Clinical and to Standard Length Implants with Sinus Grafting.
Histologic Study in Humans.
D.S. Thoma*, T.D. Taylor, A. Garcia, R. Haas, K. Sporniak-Tutak, C.H. Hämmerle
V. Kotevska*, H. Greenwell, M. Hill, A. Eskan, D. Morton, B.S. Shumway Zurich, Switzerland.
Louisville, KY.
Background: In cases with a reduced ridge height in the posterior maxilla,
Aims. Differences in the healing of demineralized and mineralized allografts sinus grafting in combination with implant placement is the treatment of choice.
have been reported but their significance has not been evaluated in ridge However, sinus grafting is associated with an increased risk for implant failures
preservation procedures. The primary aims of this study were to compare ridge and patient morbidity. Based on recent scientific evidence, short implants with
preservation using a mineralized cancellous allograft to a demineralized cortical a rough surface appear to have similar survival rates as standard length
allograft plus a PTFE barrier using clinical and histologic data to assess the implants. The use of short implants in the maxilla may therefore be a valid
outcomes. Methods. Twelve positive controls received an intrasocket treatment option avoiding major surgeries, saving time, reducing costs and
mineralized cancellous allograft (500-800 µm) while twelve test patients eliminating possible complications associated with grafting procedures. Aim:
received an intrasocket demineralized allograft (250 to 710 µm). Following tooth to compare the implant survival rates between short implants (6 mm) and
extraction and at 4-month re-entry, horizontal ridge dimensions were measured longer implants (11-15mm) in combination with sinus elevation procedures.
with a digital caliper and vertical ridge dimensions were measured from a stent. Materials and Methods: The study was designed as an open, prospective,
Each site was re-entered for implant placement at about 4 months. Prior to randomized, controlled multicenter study in 100 subjects. Subjects were
implant placement, a 2.7 X 6 mm trephine core was obtained and preserved in randomized to receive short implants or standard length implants with a sinus
formalin for histologic analysis. Results. The mean horizontal ridge width at the elevation procedure. Six months post implant placement, loading of all implants
crest of the Cancellous group decreased from 8.2 ± 1.5 mm to 6.9 ± 1.5 mm was performed. Analyzed outcome variables included implant survival rate,
for a mean loss of 1.3 ± 1.4 mm (p < 0.05) while the Demineralized group marginal bone level alterations, crown-to-implant ratio and patient-reported
decreased from 9.1 ± 1.4 mm to 6.7 ± 1.6 mm for a mean loss of 2.5 ± 1.7 mm outcomes using questionnaires (OHIP). Standard statistics were applied to
compare the treatment outcomes between test and control group. Results:

137

Oral Research Abstracts

All 100 patients had their implants placed and entered the follow-up phase esthetics (12), including recession, discoloration or infraposition. Other reasons
with loading at 6 months. No serious adverse events related to the study were crown misfit (1), crown fracture (1) or abutment change because of screw
product or study procedure were noted during and after surgery, and during loosening (1). Two of the new crowns were remade again because of esthetics(1)
the follow-up. No implants were lost resulting in a 100% implant survival rate and crown fracture(1). The most common technical complication was abutment
in both treatment groups. One minor technical complication (abutment screw screw loosening (27.1%), with 3/16 abutments showing repeated screw
fracture) in the short group occurred. The fractured screw was replaced and the loosening. Porcelain chipping occured in 3 patients (5.1%). Biologic
implant is still in function. At the time of the conference, marginal bone level complications with fistula formation were less common (5.1%) than technical
alterations between baseline (implant placement) and 6 months will be and esthetic complications. Conclusion: After more than 16 years of function,
presented. In addition, data of roughly 50 patients will be included having been all surviving implants were still supporting a functional single crown. In 75%
follow-up until 1 year post loading. Conclusions: Based on these preliminary of the cases the original crown was still in place. The main reason to renew a
findings, both treatment modalities were safe and predictable. This was crown was esthetically-driven rather than because of technical failure. The most
demonstrated by a 100% implant survival rate, the absence of biological common reversible technical complication was abutment screw loosening.
complications and only one minor technical complication.
OC-10
OC-8
Early Bone Resorption after Vertical Bone Augmentation – A Comparison
The Three-dimensional Bone Reconstruction using the Tunnel Technique: of Calvarial and Iliac Grafts.
First Results of a Retrospective Study of 5 Years of Functional Loading.
C. Mertens*, C. Decker, K. Freier Heidelberg, Germany.
A. Ponte* Rivoli (Torino), Italy.
Objective and Aim: Severe cases of bone atrophy in maxilla or mandible
In the last 15 years bone grafting became more and more a routine are often reconstructed using bone from extraoral donor sides. Most commonly,
procedure performed with different techniques; autogenous bone was mostly bone from the iliac crest is used for augmentation, however, it is frequently
used. The bone resorption in the vertical dimension was the typical problem associated with bone resorption as possible late complication. Calvarial bone
described in the literature. Aim of this study is to present a five years follow grafts are an alternative, which is often reported to show less resorption. The
up after functional loading of 3-D regenerated sites using the tunnel technique. aim of this study was to compare bone stability of vertical bone grafts from
Between 2002 and 2004 the tunnel technique procedure for 3-D bone grafting the iliac crest and the calvarium. Patients and Methods: Twenty-three patients
was performed in 32 patients. 13 patients were augmented in the upper jaw receiving vertical bone grafts were included in this study. In 9 patients alveolar
while the other 19 cases were performed in the mandible. In 31 cases bone was ridge defects were reconstructed with bone from the iliac crest. Fourteen patients
harvested from the retromolar area. No crestal incisions were done. Only one were reconstructed with bone from the calvarium. To quantify bone resoprtion,
vertical mesial muco-periostial incision was necessary to access the residual digital panographs were used for evaluation. Radiographs were taken prior to
ridge through a tunneling preparation. 16 weeks after 21 Biomet 3i and 44 bone grafting, after augmentation surgery, 3 months after bone healing, prior
Dentsply Friadent XiVE implants were inserted. In 10 cases a biopsy of the to implant surgery, after implant surgery and in yearly intervals thereafter. Results:
grafted bone was taken. The digital radiographical evaluation started after Bone grafts from the iliac crest showed a significant (p=0.0004) higher bone loss
the cementation of the definitive restorations for the following 5 years. Thus of 24.16% (SD 8.47%) than grafts from the calvarium 8.44% (SD 3.64%). Implant
the distance from the top of the implant shoulder to the beginning of the crestal survival was identical in both groups. Discussion: Although both bone-grafting
bone surrounding the implant was measured mesially and distally and approaches are successful and reliable techniques enabling implant placement
evaluated statistically. No dehiscences or signs of inflammations were registered in atrophied alveolar ridges with identical implant survival rates, bone resorption
after the interventions. No bone resorption occurred while placing the implants. in both groups differs. Bone from the calvarium shows significantly higher bone
The bone biopsies taken with the trephine bur showed a clinically well stability, especially in the early healing phase.
vascularized and regenerated bone. The histological findings showed clearly
a high presence of new bone formation, osteoid and bone marrow. The survival OC-11
rate of the implants was 100%. All the prosthetic temporary and definitive
procedures passed without signs of inflammation. Plaque was present on 35% Crestal Remodeling and Osseointegration at Surface Modified
of the implants. Bleeding on probing was detectable at 2 implants (3%). The Commercially Pure Titanium and Titanium Alloy Implants in a Canine
statistical findings showed a mean bone loss resorption after 5 years of 0,43 Model.
(SD 0,05) mm mesially and 0,63 (SD 0,4) mm distally. The major advantage of
the “tunnel technique” flap design is the avoidance of the crestal incision in C. Susin*, J. Lee, S. Hurson, H. Tadros, P. Schüpbach, U.M. Wikesjö Augusta,
order to preserve the blood supply and the integrity of the tissue. This surgical GA.
technique combined with the “biological approach” of bone grafting (scaffold
concept) may accelerate the bone regeneration process maintaining the grafted Background: To improve biological properties and mechanical strength, small
bone volume and its integrity around the implants. amounts of aluminum and niobium have been added to commercially pure
(CP) titanium. Ti-6Al-7Nb alloys exhibit enhanced mechanical properties and
OC-9 corrosion resistance. Objectives: To evaluate osseointegration and local bone
formation at anodized Ti-6Al-7Nb alloy oral implants using a canine immediate
Prosthetic Outcome and Complication Rate of Single Turned Implants loading model. Methods: Two threaded anodized CP titanium implants and two
after 16 to 22 Years of Function. anodized Ti-6Al-7Nb alloy implants were placed into each jaw quadrant in the
edentulated posterior mandible in 6 adult male Hound Labrador mongrel dogs.
M. Dierens*, S. Vandeweghe, K. Nilner, J. Kisch, H. De Bruyn Gent, Belgium. Abutments (zirconia or titanium) were placed onto the implants and the
mucogingival flaps were adapted and sutured for transmucosal wound healing
Background: Dental implants have been used for single tooth replacement and immediate implant loading. Block biopsies were collected for histometric
since the late 1980s. Little long-term studies are available about success of analysis following an 8-week healing interval. Results: Healing was uneventful.
single implants. Aim: The aim of this study is to evaluate the prosthetic outcome Mean (±SE) osseointegration reached 68.0±4.4% and 62.8±2.5% for CP titanium
and complication rate of single dental implants after 16 to 22 years of function. and Ti-6Al-7Nb alloy implants, respectively. Bone density outside and within
Materials & methods: Patients treated with single turned implants in the Dental the root of the threads amounted to 49.0±4.5% and 38.7±5.1% for CP titanium
Specialist Clinic in Malmö, Sweden, between 1987 and 1993 were recalled for implants and 43.2±3.6% and 34.2±4.8% for Ti-6Al-7Nb alloy implants. Crestal
a clinical investigation. Prosthetic parameters were evaluated based on patients’ resorption averaged 0.4±0.1 mm for both CP titanium and Ti-6Al-7Nb alloy
files, clinical measurements and interviews. Results: 50 patients who initially implants. There were no statistically significant differences between implants
received 62 implants attended the investigation. 3 implants had failed in 2 for any parameter assessed. Notably, advanced buccal crestal resorption exposing
patients. The cumulative implant survival rate of all treated patients was 91.5% the implant threads was observed in at least 45% of the implants (4 of 6 animals)
after 16 years. The mean follow-up of the current patient group was 18.4 years. regardless of implant technology; active resorption still observed at 8 weeks
Abutments of the 59 surviving implants were customized titanium abutments following implant placement. Conclusion: Anodized Ti-6Al-7Nb alloy implants
(22) or CeraOne (37). During follow-up 8 customized (36.4%) and 4 CeraOne may be considered viable alternatives to benchmark anodized CP titanium
abutments (10.8%) have been replaced. 11 new abutments were CeraOne and implants. Remodeling of the buccal crestal plate resulting in advanced bone loss
one crown was remade on implant level. Materials of the crowns at baseline appears a major impediment to oral implant osseointegration and in extension
were porcelain-fused-to-metal (23), all-ceramic (33) or acrylic (3). In total 15/59 possibly implant maintenance.
crowns (25.4%) were remade. The main reason for crown renewal (80%) was

138

Oral Research Abstracts

OC-12

Split-Mouth Comparison of Accuracy for Computer-Generated Versus
Conventional Surgical Guides.
N.E. Farley*, N. Clelland, E. McGlumphy, K. Kennedy La Crosse, WI.

Purpose: Recent clinical studies have shown that implant placement is highly
predictable with computer generated guides; however, reliability of these guides
has not been compared to conventional guides clinically. This study aimed to
compare the accuracy of reproducing planned implant positions between
computer generated and conventional surgical guides in a split-mouth design.
Materials and Methods: A total of 13 patients received 2 implants bilaterally.
CBCT scans were taken with scan appliances, utilizing gutta percha markers as
reference points. All implants were planned virtually. Patients were randomly
selected for CAD/CAM guided implant placement on one side. Conventional
guides were used on contralateral sides. Patients received post-operative CBCT
scans with the same scan appliance. The gutta percha markers were used to
relate the implant placement to the initial planning. This allowed for comparison
capable of measuring volume overlap, differences in angles, coronal, and apical
positions. Results were compared using a Mixed Model Repeated Measures
ANOVA and Bartlett’s test for unequal variance (alpha = 0.05). Results: Implants
placed with CAD/CAM and conventional surgical guides had volume overlaps
between planned and actual positions of 69.7% ± 6.8% and 48 ± 16.2%,
respectively. This was a statistically significant difference (p < 0.05). Coronal
horizontal differences also showed significance (p < 0.05) with CAD/CAM
measuring at 0.55 mm ± 0.24 mm and conventionally guided implants at 1.22
mm ± 0.62 mm. Apical horizontal distance significantly (p < 0.05) showed
CAD/CAM to be more accurate than conventional guides (0.93 mm ± 0.62 mm
and 2.03 mm ± 0.95 mm, respectively). Other measurements made did not show
statistical significance. Statistical analyses showed that accuracy was not related
to bone density, implant width, or implant length. Conclusion: Implants placed
using CAD/CAM surgical guides provided more accuracy in a lateral direction
than conventional guides. In addition, CAD/CAM guides were more consistent
in their deviation from the planned placements than conventional guides. This
study was supported in part by Biomet 3i.

139

Clinical Innovations Abstracts

CI-1 traditional waxing and casting techniques and offer the patient an excellent
outcome. Team planning and fabrication techniques will be discussed for several
2.5mm Diameter Mini-implant with Dual Connection Mechanisms for mandibular reconstruction patients. The presentation will demonstrate the
Abutment: Preliminary Test and Clinical Cases. unique advantages of custom designed and milled healing abutments,
CAD/CAM fabricated titanium frameworks and titanium laser assembling
K. Choi* Busan, Republic of Korea. techniques for these very difficult situations. Several of the patients presented
have 3-5 year clinical/radiographic follow-up.
Dental implant with diameter 3mm or less is usually made in uni-body
construction that has inseparable abutment and fixture components. Uni-body CI-3
design is a reasonable solution for mini-implant for structural strength, but it
compromises the prosthetic outcome since restorative options are quite limited. New Scalloped Implant with Platform Switching and Micro-thread:
Few years ago, mini-implant that has separate abutment system utilizing friction- Design Theories and Applications.
lock connection was introduced. This system uses a mallet to connect abutment
to mini-implant via friction-lock and has proven the connection to be reliable. S. Chung*, K. Choi Busan, Republic of Korea.
Despite malleting method is proven to be clinically reliable, abutment friction-
lock connection is variably dependent on factors such as mallet weight, number Limited studies on first generation scalloped implant showed unfavorable
of mallet tapped, speed of mallet used, and so on. Thus, more consistent method peri-implant bone loss compared to conventional flat-top implants. However,
other than using a mallet to connect the abutment to mini-implant is sought no clear explanation or the remedy for bone loss problem in first generation
after. New connection mechanism to mini-implant is innovated so that scalloped implant is yet to be provided. New scalloped implant design is
conventional torque driver can be used for the friction-lock abutment proposed with platform switching and micro-thread features. Reasons for such
connection. This new design allows dual methods, either mallet or torque driver, design proposal is that platform switching redirects the loading stress away from
for the mini-implant and abutment connection. At the Academy of periphery of bone-implant interface to the center of implant body to protect
Osseointegration 2012 Annual Meeting, we would like to present dual abutment the bone from resorption, in addition to making a restorative dentist to control
connection mechanism to 2.5mm diameter mini-implant and share the the prosthetic margin level on abutment. Micro-thread creates heterogeneous
preliminary test results of this new connection and how it is actually utilized stress field in bone-implant interface, converting unfavorable tensile and shear
in clinical situations. forces acting on bone to more favorable compressive force, thus reducing the
overall unfavorable forces for improved marginal bone preservation, in addition
to increasing the bone-implant interface surface area. Theoretical proposition
of new scalloped implant design was experimented in canine model. In this
study, new scalloped implant design was compared to external-hex flat-top
implant design without loading in healed sites. Proximal bone resorption in new
scalloped implant design was statistically significantly less than conventional
flat-top implant (Choi et al, 2010.) In order to understand the loading stress of
scalloped implant, various scalloped implant designs were studied in 3
dimensional finite element analysis, including model similar to first generation
scalloped implant. Loading stress of scalloped implant was distinctive with
different designs. Platform switching connection seemed more predominant
factor to reduce occlusal load transmitted to surrounding bone than the designs
of micro-thread in scalloped implant. Micro-thread design in scalloped implant
had different influence on loading stress in bone (Choi et al, manuscript
accepted.) New scalloped implant design is clinically applied. Clinical appearance
of soft tissue response to new scalloped implant is observed and radiographic
examination record is being collected. Preliminary results of marginal bone
loss of new scalloped implant seem equivalent to flat-top implant with platform
switching and micro-thread design. New scalloped implant appears to have
more latitude for manipulating mid-facial gingiva to more apical position.

CI-2 CI-4

The Advantages of CAD/CAM Prosthetic Reconstruction of Implants in Direct Laser Metal Forming (DLMF) Implants: Results from a 1-year
the Severely Damaged Mandible. Prospective Nulticenter Study.

R. Schneider*, K. Fridrich, G. Funk, K. Chang Iowa City, IA. G. Luongo*, F. Luongo, F. Mangano, C. Mangano Naples, Italy.

Destruction from acquired oromandibular defects can be devistating. Background: In the last few years considerable progress has been made in
Prosthetic and surgical rehabilitation of these defects is at best a very difficult the development of rapid prototyping (RP) methods, including direct laser metal
challenge. Microvascular surgical techniques, dental implants and forming (DLMF). DLMF is a timesaving and costless metal forming procedure
advancements in dental technology provide a sound foundation that can create in which a high power laser beam is focused on a metal powder bed and
a more favorable restorative, functional and aesthetic morphology. This can programmed to fuse particles according to a CAD file, thus generating a thin
provide the prosthodontist the opportunity to restore the patient with a metal layer. Apposition of subsequent layers gives shape to a desired three-
partially or totally resected mandible with an implant anchored prosthesis that dimensional form with the need of minimal post-processing requirements. Aim:
is nearly as functional as the natural dentition. Prosthetically a problem with This prospective multicenter study evaluated the survival rate and the implant-
the thick skin paddles from the fibula or scapula graft is obtaining adequate crown success of direct laser metal forming (DLMF) titanium dental implants
tissue healing with the available standard height healing abutments when (TixOsR, Leader Novaxa, Milano, Italia) in different clinical applications, after
utilizing the single stage surgical implant placement approach. Traditionally 1-year of functional loading. Materials and methods: At the 1-year scheduled
the option of a two stage surgical technique was the routine treatment protocol. follow-up examination, several clinical, radiographic and prosthetic parameters
Today many implants are placed utilizing the single stage placement technique. were assessed. Success criteria included absence of pain, sensitivity, suppuration,
The use of CAD (computer aided design) scanning and CAM (computer aided exudation; absence of clinically detectable implant mobility; absence of
milling) milling to fabricate custom healing caps up to 18 mm in height has continuous peri-implant radiolucency; distance between the implant shoulder
proven to be a significant advantage when utilized through the myo-cutaneous and the first visible bone contact (DIB) < 1.5 mm; absence of prosthetic
grafts from the fibula or scapula. CAD/CAM or titanium laser assembled complications. Results: 201 implants (106 maxilla, 95 mandible) were placed
components and the resulting restorations are superior in many ways to in 62 patients (39 males, 23 females; aged between 26-65 years) in 8 different
clinical centers. The sites included anterior (n=79) and posterior (n=122)
140 implants. The prosthetic restorations comprised 105 single crowns, 45 fixed
partial prostheses and 2 fixed full-arch prostheses. After 1-year of functional
loading, the overall implant survival rate was 99.5%, with one implant loss
(maxilla: 99.0%; mandible: 100.0%). The mean distance between the implant

Clinical Innovations Abstracts

shoulder and the first visible bone contact (DIB) was 0.4 mm (± 0.2). Among CI-6
the surviving implants (200), 5 did not fulfil success criteria, for an implant-
crown success of 97.5.%. Conclusions: Direct laser metal forming (DLMF) Evaluation of a Trabecular Metal Dental Implant Design for Primary
implants seem to represent a valid treatment option for rehabilitation of partial Stability, Structural Integrity and Abrasion.
or completely edentolous patients.
S. Battula*, S. Papanicalaou, H. Wen, M. Collins Carlsbad, CA.
CI-5
Introduction: Trabecular metal (TM) has been used in to facilitate medical
Surgical Protocol and Short-term Clinical Outcome of Immediate implant anchorage by allowing 3-dimensional bone ingrowth and ongrowth.
Placement in Molar Extraction Sockets using a Wide body Implant. A 3-part dental implant assembly has been designed with a TM shell in its
A.C. Hattingh*, S. Vandeweghe, A. Wennerberg, H. De Bruyn Sevenoaks, midsection. Study objectives were to (1) evaluate the primary stability of this
United Kingdom. implant design, (2) determine the effects of abrasion on its TM section during
placement, and (3) evaluate the overall structural integrity of the implant
The immediate placement of dental implants into single or double rooted assembly. Methods: Five tapered screw implants with an apical vent (control)
extraction sockets has been well described and is widely used. However and TM implants of 4.1, 4.7 & 6.0mm diameters were placed into dense artificial
techniques to address the 3 rooted sockets of molar teeth are not as common bone material according to recommended drilling sequence and insertion
and appear to be less frequently used. Aim: to evaluate retrospectively the torque (IT) was measured to determine implant stability. To evaluate the effects
outcome of an 8-9 mm diameter tapered implant, designed to be placed in of abrasion, three implants of each diameter were placed into osteotomies
molar extraction sockets and to describe the technique used to place this type created in both dense artificial bone and bovine bone condyles. Implants were
of implant. Materials and methods: Patients treated at least 1 year before with microscopically evaluated to identify any damage to the implant surface. Six
a Max® implant (Southern Implants, Irene, South Africa) were invited for a clinical TM implants (4.1mm diameter) were each placed into artificial bone materials
examination. Variables collected were surgical and prosthetic protocol, implant and mechanically pulled out. Results: Mean IT values, recorded using a torque
dimension and smoking habits. Peri-implant bone level was determined on meter, for both control and TM implants were 95.0±3.0 & 96.0±7.9Ncm for
peri-apical radiographs and compared to baseline, immediately after implant 4.1mm implants, 114.3±4.8 & 109.1±3.1Ncm for 4.7mm implants, and 157.9±21.2
insertion. Results: In total, 89 patients representing 98 immediately placed & 161.1±5.7Ncm for 6.0mm implants, respectively. Statistical analysis indicated
implants were invited for examination. One implant had failed, resulting in a that control and test implants did not differ significantly for IT (p=0.494, 0.596
survival rate of 99%. 38 patients representing 47 implants (26 maxilla, 21 & 0.679). Microscopic evaluation of the TM implant prior to and after implant
mandible) were available for clinical examination. All implants reached a stability placement in dense artificial bone and bovine condyles revealed that the struts
of over 50Ncm when placed. Mean bone loss was 0.38 mm (SD 0.48; range - and pores within the field of view remained fully intact. No cracks were found
0.50 – 1.95) after a mean follow-up period of 20 months (SD 5.75; range 12-35). visually on the surface of TM at 24, 65 & 137× magnifications (Fig 1). Structural
Overall implant success according to Albrektsson & Zarb (1994) was 97.9%. integrity of the test implants was evaluated per the pullout tests which yielded
Around 30 implants, a bone substitute was used to fill the residual space. Bone 313.3±34.3N & 1571.9±44.4N in simulated cancellous and cortical bone materials
loss was only significantly different between maxilla and mandible (0.48 mm respectively, and no part of the implant assembly failed. Conclusion: The new
vs 0.27 mm) and between the 8 and 9 mm diameter implants (0.23 mm vs 0.55 TM dental implant exhibited insertion torque values similar to those of the
mm). A full papilla was present at 71% of the interproximal sites. Conclusion: tapered screw implants. Insertion torque has been reported to have a strong
The Max® implant demonstrated good primary stability when placed in molar correlation to primary stability. The TM implant was able to maintain its
extraction sockets, with limited bone loss over time. This innovative technique structural integrity to withstand normal range of clinical functions.
can be used with a high degree of predictability and success, to remove and
replace molar teeth in a much shorter time than conventional methods.

Single molar replacement with an immediate placement protocol. Microscopic images of the TM dental implant, with porous tantalum material, prior
to implantation and after removal of implant from bovine condyle

141