Abstracts Implantology 1
Abstracts Implantology 2
Miracle of CaOH
Extra-oral fistula in nostril |
Use of antibiotics
10 myths about latex allergy
01. An In Vitro Analysis of Implant Screw Torque Loss With External Hex and Internal Connection Implant Systems 02. Complications of Intraoral Donor Site for Bone Grafting Prior to Implant Placement. 03. Implant-Supported Prosthetic Applications Upon Development of Children and Adolescents: A Pilot Study in Pigs. 04. Position of the Mental Foramen in a Korean Population: A Clinical and Radiographic Study 05. Survival of Immediately Loaded Dental Implants in Deficient Alveolar Bone Sites Augmented with [beta]-Tricalcium Phosphate 06. Bone Regeneration Around Implants Using Spherical and Granular Forms of Bioactive Glass Particles. 07. Effect of Glucocorticoid-Induced Osteoporotic-Like Conditions on Osteoblast Cell Attachment to Implant Surface Microtopographies 08. Saliva and Dental Implants 09. Rehabilitation of Maxillary Edentulism With Implant-Supported Milled-Bar Prostheses. 10. De Novo Grown Bone on Exposed Implant Surfaces Using Photodynamic Therapy and Recombinant Human Bone Morphogenetic Medical Contraindications to Implant Therapy: Part I: Absolute Contraindications. 11. A Cast Metal Core for a Deformed Implant Body: Case Report. 12. Dental Implant Success-Failure Analysis: A Concept of Implant Vulnerability 13. Piezosurgery: Basics and Possibilities. 14. Consensus Conference on Immediate Loading: The Single Tooth and Partial Edentulous Areas. 15. Benefits of an Implant Platform Modification Technique to Reduce Crestal Bone Resorption 16. Histologic Evaluation of 3 Retrieved Immediately Loaded Implants After a 4-Month Period 17. Bacterial Plaque Colonization Around Dental Implant Surfaces 18. Measuring Mobility of 2 Dental Implant Fixtures of Different Configurations: An In Vitro Study 19. Reconstruction of a Mandibular Critical-Sized Defect Using Iliac Graft in Rats 20. Increasing the Width of Keratinized Mucosa Around Endosseous Implant Using Acellular Dermal Matrix Allograft 21. Heterotopic Bone Formation Around Sintered Porous-Surfaced Ti-6Al-4V Implants Coated with Native Bone Morphogenetic Proteins. 22. Finite Element Analysis of Different Bone Substitutes in the Bone Defects Around Dental Implants 23. Dentin Dysplasia Type I Treated with Onlay Bone Grafting, Sinus Augmentation, and Osseointegrated Implants 24. Prosthetic Rehabilitation of a Bone Defect with a Teeth-Implant Supported, Removable Partial Denture 25. Plastic Temporary Abutments with Provisional Restorations in Immediate Loading Procedures: A Clinical Report 26. Bone Marrow Aspiration: Technique, Grafts, and Reports 27. Vertical Bone Augmentation: Where Are We Now? 28. Dental Endosseous Implants in Patients on Bisphosphonate Therapy.
An In Vitro Analysis of Implant Screw Torque Loss With External Hex and Internal Connection Implant Systems. Implant Dentistry. 15(4):427-435, December 2006. Jack Piermatti, DDS; Hoda Yousef, DMD, MS; Allyn Luke, BSE, MSE; Richard Mahevich, DMD; Saul Weiner, DDS Abstract: Purpose: The purpose of this study was to examine, in a controlled environment, effects of connection design upon screw stability. Implant fixtures have 2 types of connections to the abutment: internal connection and external hex. Four implant systems were tested: Bio-Lok (external hex; Bio-Lok International, Inc., Deerfield Beach, FL); Zimmer (internal connection; Zimmer Dental, Carlsbad, CA); Nobel Biocare (external hex; Nobel Biocare USA, Inc., Yorba Linda, CA); and Astra Tech (internal connection; Astra Tech Inc., Waltham, MA). Materials and Methods: Ten samples of each system, including base, implant, abutment, and molar crown, were loaded to 200 N for 1 x 106 cycles. Screws were tightened to manufacturers' recommendations,and torque audits done at 2.5 x 105, 5 x 105, 7.5 x 105, and 1 x 106 cycles. Results: The Bio-Lok samples lost an average of 10% of the original torque values, the Astra Tech group lost almost all of the torque and loosened, while the Zimmer and Nobel Biocare samples lost an average of 50% of the torque but did not loosen (P <= 0.05). Conclusions: It may be concluded from this study that although internal connections are clinically favored, this study did not show any advantage relative to screw loosening. However, screw design may be a significant factor in loosening of the joint. Complications of Intraoral Donor Site for Bone Grafting Prior to Implant Placement Implant Dentistry. 15(4):420-426, December 2006. Fabrício Moreira Serrae Silva, DDS, MS; André Luís Vieira Cortez, DDS, PhD; Roger William Fernandes Moreira, DDS, PhD; Renato Mazzonetto, DDS, PhD Abstract: Purpose: The purpose of this prospective study was to evaluate the morbidity and the major complications of intraoral donor sites for bone grafting prior to implant placement. Materials: The records of 104 consecutive patients with indication for bone grafting prior to implant installation treated at Piracicaba Dental School by the Department of Oral and Maxillofacial Surgery, from June 2001 until June 2003, were reviewed. Results: One hundred three surgical procedures were realized, in which 40% were harvested from mandibular symphysis, 28.8% from mandibular ramus, and 31.2% from maxillary tuberosity. Prevalence of complications among intraoral donor sites was more significant after harvestingvesting the mandibular symphysis. The major complication and discomfort reported by the patients was sensory deficit in lower lip and mental area. It was noted that 16% harvesting procedures involving symphysis and 8.3% involving the mandibular ramus area reported some sensory deficit. No complications were found involving the maxillary tuberosity. Conclusion: Complications and morbidity were smaller in the ramus than in symphysis, and temporary sensory disturbances were the most common complications, noted in both symphysis and ramus areas. Implant-Supported Prosthetic Applications Upon Development of Children and Adolescents: A Pilot Study in Pigs. Implant Dentistry. 15(4):412-419, December 2006. Ahmet Ersan Ersoy, DDS, PhD; Demet Bendik Ellialti, DDS, PhD; Necdet Dogan, DDS, PhD Abstract: Purpose: The purpose of this study is the investigation of the application of implant-supported prosthetic restorations using 2 implants supporting a fixed prosthesis during the physical growth and the development period of growing pigs. Materials and Methods: This study was carried out on 6 male farm pigs (1 as a control). The effect of the 2 screw-type endosseous implants inserted into the premolar area on the left mandibular arches of 5 farm pigs upon the jaw was investigated during a 3.5-8-month growth period using cephalometric radiographs. The cephalographs were taken with a specially standardized cephalostat, and asignificant test of differences between 2 partners was used to evaluate them. Results: The study suggested that the implants showed alveolar elevation by bone growth but could not keep pace with the natural teeth eruptions and the bone growth in the region. Conclusion: Although the sagittal and transverse developments of the neighboring bone region are greater than the implant-inserted region, the difference in this growth can be tolerated by corrections or modifications of implant- supported superstructures. Position of the Mental Foramen in a Korean Population: A Clinical and Radiographic Study Implant Dentistry. 15(4):404-411, December 2006. In-Soo Kim, DDS, BSc, MSD, PhD; Su-Gwan Kim, DDS, MSD, PhD; Young-Kyun Kim, DDS, MSD, PhD; Jae-Duk Kim, DDS, MSD, PhD Abstract: Purpose: The purpose of this study was to improve the treatment methods for the mental foramen by comparing the directly measured values with the radiographic measured values. Materials and Methods: One hundred and twelve mental foramina (72 males, 40 females) that were exposed during the operation were examined. The patients' age ranged from 12 to 69 years, with a mean age of 41.8 years. All patients had fully erupted lower premolars. The horizontal and vertical locations were evaluated with both direct and radiographic measurements. Results: In 72 patients (64.3%), the mental foramen was below the second premolar. In 26.8%, it was between the first and second premolar, and in 8.9%, it was below the first premolar. By radiographic readings,most of the mental foramina were found to be below the second premolar (62.5%). The average distance between the cusp tip and the superior border of the mental foramen by direct measurement was 23.42 mm and 25.69 mm in the panoramic view. The mean distance between the superior border of the mental foramen and the bottom of the mandible was 14.33 mm by direct measurement and 16.52 mm by radiographic measurements. Conclusion: It is important to know the position of the mental foramen for the placement of osseointegrated implants in the mandibular premolar region. The position of the mental foramen of Koreans is closer to the cusp tips of lower premolars than Westerners. Survival of Immediately Loaded Dental Implants in Deficient Alveolar Bone Sites Augmented with [beta]-Tricalcium Phosphate. Implant Dentistry. 15(4):395-403, December 2006. Zeev Ormianer, DMD; Ady Palti, DMD; Arie Shifman, DMD Abstract: Purpose: Dental implant placement in atrophic alveolar ridges often necessitates grafting procedures, followed by immediate or delayed implant placement. This study assessed the survival of immediately loaded dental implants placed in deficient alveolar bone sites at bone grafting. Materials: From 1999 to May 2002, 1 operator (A.P.) inserted 1065 implants (607 in mandibles, 458 in maxillae) into 338 partially edentulous patients. Most implants were placed into compromised residual ridges or prepared tooth extraction sockets. Implants placed in augmented areas were splinted to implants in nonaugmented sites for stability. In all cases, [beta]-tricalcium phosphate was mixed with blood from the surgical site to augment the ridge level or fill spaces between the implant and socket wall. When indicated, the same materials were used for sinus floor augmentation. All implants were tapered screws with roughened surfaces, primarily (75%) from 1 manufacturer. One of the authors (Z.O.) prosthetically restored a total of 189 implants that were placed in 35 patients. In this group of patients, complete restorative data were available. All implants were monitored for 12-48 months (mean = 19.2; median = 24). Results: A total of 1039 implants survived, and 26 failed, including 5 in the anterior mandible and 21 in the maxillae. In the restorative group, 186 implants survived, and 3 maxillary implants failed. All implant failures in this study occurred in the augmented sites. Conclusion: Within the limitations of this study, immediate loading of splinted implants in augmented sites is a predictable procedure. Bone Regeneration Around Implants Using Spherical and Granular Forms of Bioactive Glass Particles Implant Dentistry. 15(4):386-394, December 2006. Alexander A. Veis, DDS; Nikolaos N. Dabarakis, DDS; Nikolaos A. Parisis, DDS; Anastasios T. Tsirlis, DDS; Theodora G. Karanikola, DDS; Dimitra V. Printza, DDS Abstract: Purpose: It has been reported that previous Biogran(R) (3i Implant Innovations, Inc., Palm Beach Gardens, FL) can be converted in vitro into hydroxyapatite (Biogran II(R)) to accelerate new bone formation. The purpose of this study was to evaluate the bone regeneration around implants placed in critical-sized defects in rabbit tibia using granular and spherical forms of Biogran II(R) in regards to implant contact, bone-to-graft contact, bone graft area, and total bone volume. Materials and Methods: Twelve adult New Zealand rabbits were used, offering 24 surgical sites (1 in each tibia), where 6-mm round defects were created allowing the homocentric insertion of a screw type experimental implant with Osseotite(R) (3i Implant Innovations, Inc.) surface. Half of the defects (group A) were filled up with spherical and half (group B) with granular forms of Biogran II(R). Ossix(R) (3i Implant Innovations, Inc.) membranes covered the surgical sites. Results: The histological evaluation after 8 weeks showed new bone formation in both groups, without any statistically significant differences in regards to bone-to-implant contact, bone-to-graft contact, bone graft area, and bone volume. Both dissolution of the outer shell and inner silica gel of the particles were observed mostly in spherical particles. In addition, new bone formation within the protected pouch interconnected with the surrounding new bone was observed exclusively in spherical particles of Biogran II(R). Conclusion: Faster dissolution of both outer and inner portions of spherical particles of Biogran II(R) led to better integration with the surrounding new bone during an 8-week period of healing. Effect of Glucocorticoid-Induced Osteoporotic-Like Conditions on Osteoblast Cell Attachment to Implant Surface Microtopographies Implant Dentistry. 15(4):377-385, December 2006. Peter Cho, DDS; Galen B. Schneider, DDS, PhD; Bradley Kellogg, DDS; Rebecca Zaharias, BS; John C. Keller, PhD Abstract: Objectives: The objectives of this work were to: (1) establish methodology for pretreating osteoblast-like cells in vitro with dexamethasone to cause glucocorticoid-induced osteoporosis, (2) perform quantitative and qualitative assessments of cellular attachment of osteoporosis-like osteoblasts when grown on implant surfaces of differing roughness, (3) and explore the hypothesis that dexamethasone-treated osteoblasts have altered cell attachment properties by focal adhesion disassembly and decreased tyrosine phosphorylation of the focal adhesion tyrosine kinase. Methods: Osteoblasts were cultured with dexamethasone (10-7 and 10-6 M) for up to 4 days of incubation to induce osteoporosis-like conditions. Cellular attachment assays demonstrated the effect of dexamethasone treatments on cellular attachment properties of osteoblasts. Qualitative data were obtained utilizing immunofluorescent microscopy and Western blotting. Focal adhesion kinase (FAK) immunoprecipitation and tyrosine-phosphorylation Western blots were obtained from dexamethasone-treated human embryonic palatal mesenchymal- 1486 osteoblast cultures supplemented with ascorbate and [beta]-glycerol phosphate medium. Results: Cellular attachment was significantly greater (P < 0.05) with non-dexamethasone-treated osteoblasts (92%) as compared todexamethasone-treated osteoblasts after 1 (72%), 2 (63%), and 4 days (53%) of exposure. Dexamethasone- treated osteoblasts were viable and capable of proliferation, suggesting that the reduction of cellular attachment may be related to these cell adhesion processes. Immunofluorescent microscopy of both dexamethasone-treated osteoblasts and non-dexamethasone-treated osteoblasts failed to show any relative difference in the disassembly of focal adhesions and actin filaments. Extended dexamethasone treatment periods (up to 3 weeks) showed changes in the levels of FAK and FAK- phosphotyrosine in human embryonic palatal mesenchymal-1486 osteoblasts. Conclusions: The protocol used in this study demonstrated a glucocorticoid-induced osteoporosis-like suppression of osteoblasts. FAK disassembly was not a significant factor in short period; however, FAK protein levels and phosphotyrosine signaling on FAK were affected after 1-week exposure to dexamethasone. Phosphorylated FAK was not associated with the rise in the level of FAK, further indicating the possibility of FAK involvement in reduced cell attachment. Saliva and Dental Implants Implant Dentistry. 15(4):372-376, December 2006. Fotoula Nikolopoulou, DDS, MD, Dr. Dent, MPH Abstract: This is a review and update of the: (1) interaction of dental implants with the environment, and (2) effects of salivary contamination on the load of implant prostheses. Rehabilitation of Maxillary Edentulism With Implant-Supported Milled-Bar Prostheses Implant Dentistry. 15(4):366-371, December 2006. Fabiana Gouveia Straioto, DDS; Alessandra Miranda de Azevedo, DDS; Célio Jesus do Prado, DDS, MS, PhD; Flávio Domingues das Neves, DDS, MS, PhD; Alfredo Júlio Fernandes Neto, DDS, MS, PhD Abstract: Implantology has allowed more options for rehabilitation of complete and partially edentulous patients. The professional should describe all possible alternatives to the patient, addressing all the positive and negative aspects of each possibility, such as treatment time, complexity of surgical procedures, and the final cost. The patient should select the best cost-benefit relationship because fixed prostheses are often not the option of choice for the patient. The aim of this article is to present one possible treatment option for the completely edentulous patient by use of implants to support and retain a removable complete or partial prosthesis. The clinical situations were rehabilitated by the use of a milled bar screwed to the implants to support a removable prosthesis with attachments and a milled metallic groove, which provide many advantages to the patient. De Novo Grown Bone on Exposed Implant Surfaces Using Photodynamic Therapy and Recombinant Human Bone Morphogenetic Protein-2: Case Report Implant Dentistry. 15(4):361-365, December 2006. Karl-Heinz Schuckert, DMD, MD, PhD; Stefan Jopp, MD, PhD; Ulrich Muller, DMD, PhD Abstract: The reconstruction of bone on exposed implant surfaces requires an almost complete elimination of attached bacteria. Only then is new bone growth possible. This case report describes a new way to kill biofilms with photodynamic therapy and to augment bone by using recombinant human bone morphogenetic protein-2. Though the newtechnique of bone tissue engineering causes some problems, new bone growth on uncovered implant surfaces is successful to a large extent. Medical Contraindications to Implant Therapy: Part I: Absolute Contraindications. Implant Dentistry. 15(4):353-360, December 2006. Debby Hwang, DMD; Hom-Lay Wang, DDS, MSD Abstract: In order to ensure implant success, it is essential to select patients who do not possess local or systemic contraindications to therapy. Hence, it is the purpose of this paper to review the medical diseases that reportedly preclude conventional dental implant treatment. Absolute contraindications to implant rehabilitation include recent myocardial infarction and cerebrovascular accident, valvular prosthesis surgery, immunosuppression, bleeding issues, active treatment ofmalignancy, drug abuse, psychiatric illness, as well as intravenous bisphosphonate use. Any of these conditions bar elective oral surgery, and require judicious monitoring by the physician as well as the dental provider. Noncompliance to the suggested protocol may, in the worst possible case, result in patient mortality. A Cast Metal Core for a Deformed Implant Body: Case Report Implant Dentistry. 15(4):347-352, December 2006. Kohyoh Soeno, DDS, PhD; Ryo Jimbo, DDS; Takashi Sawase, DDS, PhD; Yohsuke Taira, DDS, PhD Abstract: The present report consists of a clinical evaluation of an osseointegrated implant using a cast metal core instead of abutment for a deformed implant body. The intramobile connector insert for the implant in the mandibular left first premolar region broke 7 years after the superstructure was attached to the implant system. The intramobile connector insert was replaced, and the prosthesis was reattached, but the new intramobile connector insert broke again 2 weeks later. A thorough examination confirmed deformation of the upper section of the implant body in the mandibular left first molar region. Breakage of the new intramobile connector insert in the mandibular left first premolar region was believed to be due to deformation of the implant body in the mandibular left first molar region. Therefore, a cast metal core was used to deal with the deformation of the implant body in this region. Although slight bone resorption was observed around the implant body after 5 years, no major problems were found in the implant body itself. Dental Implant Success-Failure Analysis: A Concept of Implant Vulnerability Implant Dentistry. 15(4):341-346, December 2006. Len Tolstunov, DDS
Abstract: This article shows the factors of importance in the long-term success and failure of oral implants based on literature review. Many factors are attributed to the failure of dental implants. The critical components leading to early and late implant failures are evaluated. The behavior of natural teeth and implants is compared in healthy and unfavorable local and systemic conditions. Similarities and differences among dental implants, healthy natural teeth, and ankylosed teeth are examined. Based on this comparison, the author attempts to draw a conclusion on the vulnerability of dental implants and their prognosis. The importance of ongoing clinical supervision of a patient's implant condition with a good recall program and the necessity to accumulate clinical data concerning implant failures over an extended period of time in a standardized manner are emphasized. It is also suggested that implant practitioners avoid giving guarantees of long-term implant success to their patients. Piezosurgery: Basics and Possibilities Implant Dentistry. 15(4):334-340, December 2006. Markus Schlee, DDS; Marius Steigmann, Dr.medic stom; Emanuel Bratu, DMD; Arun K. Garg, DMD Abstract: Useful in a variety of oral surgery procedures, piezosurgery has therapeutic features that include a micrometric cut (precise and secure action to limit tissue damage, especially to osteocytes), a selective cut (affecting mineralized tissues, but not surrounding soft tissues), and a clear surgical site (the result of the cavitation effect created by an irrigation/cooling solution and oscillating tip). Because the instrument's tip vibrates at different ultrasonic frequencies, since hard and soft tissues are cut at different frequencies, a "selective cut" enables the clinician to cut hard tissues while sparing fine anatomical structures (e.g., schneiderian membrane, nerve tissue). An oscillating tip drives the cooling-irrigation fluid, making it possible to obtain effective cooling as well as higher visibility (via cavitation effect) compared to conventional surgical instruments (rotating burs and oscillating saws), even in deep spaces. As a result, implantology surgical techniques such as bone harvesting (chips and blocks), crestal bone splitting, and sinus floor elevation can be performed with greater ease and safety. Consensus Conference on Immediate Loading: The Single Tooth and Partial Edentulous Areas Implant Dentistry. 15(4):324-333, December 2006. Hom-Lay Wang, DDS, MSD; Zeev Ormianer, DMD; Ady Palti, DMD; Morton L. Perel, DDS, MScD; Paolo Trisi, DDS, PhD; Gilberto Sammartino, MD, DDS Abstract: Purpose: A consensus conference was held to determine what the parameters should be for the immediate functional loading of the single-tooth implant restoration and short-span fixed implant-supported bridgework. Materials: Forty-one clinicians and researchers presented cases and situations relating to the topic. A panel then distilled questions that were presented to the audience (430) at large. Answers were gleaned to formulate a consensus. Results: Ten distinct answers evolved that constituted the essence of guidelines for clinicians to be aware of when undertaking immediate loading. These guidelines are contained within the body of the text. Conclusions: Extreme caution and adherence to a universal generic protocol are suggested for clinicians who are involved with single-tooth and short-span multiple-teeth implant replacements as related to immediate loading as defined within this text. Benefits of an Implant Platform Modification Technique to Reduce Crestal Bone Resorption Implant Dentistry. 15(3):313-320, September 2006. Xavier Vela-Nebot, MD, DDS; Xavier Rodríguez-Ciurana, MD; Carlos Rodado-Alonso, MD; Maribel Segalà-Torres, MD, DDS Abstract: Purpose: The alveolar bone resorption that occurs around a 2-piece implant following abutment attachment is a well- documented observation. Several investigators propose that crestal bone loss is a response to the invasion of the biologic width by secondary bacterial colonization and micromovements at the implant-abutment interface. This study proposes the creation of a difference between the diameter of the implant platform and diameter of the abutment (implant platform modification), shifting the implant-abutment interface medially to minimize invasion of the biologic width. Material and Methods: We present a series of 30 control cases and 30 study cases using the platform-modification technique. Interproximal bone resorption on the medial and distalof each implant was assessed using digital radiography at 1, 4, and 6 months after abutment attachment. Results: The mean value of bone resorption observed in the mesial measurement for the control group was 2.53 mm, whereas for those patients included in the study group, it was 0.76 mm. The mean value of bone resorption observed in the distal measurement for patients in the control group was 2.56 mm, whereas for those included in the study group, it was 0.77 mm. Conclusions: All patients in the study group had a significant reduction of bone loss in comparison to the control group (P < 0.0005). Histologic Evaluation of 3 Retrieved Immediately Loaded Implants After a 4-Month Period Implant Dentistry. 15(3):305-312, September 2006. Giovanna Iezzi, DDS, PhD; Gabriele Pecora, MD, DDS; Antonio Scarano, DDS, MD; Vittoria Perrotti, DDS, PhD; Adriano Piattelli, MD, DDS Abstract: Objective: To perform a histologic and histomorphometric analysis of the peri-implant tissue reactions and bone- titanium interface in 3 immediately loaded (provisional loaded) titanium implants retrieved from a man after a loading period of 4 months. Materials & Methods: A 35-year-old patient with a maxillary partial edentulism did not want to wear a provisional removable prosthesis during the healing period. It was decided to insert 3 definitive implants and use 3 provisional implants for the transitional period. The provisional implants were loaded the same day with a resin prosthesis in occlusal contact. During the second surgical phase, after 4 months, the provisional prosthesis was removed, and the provisional implants were retrieved with a trephine bur. Before retrieval, all implants appeared to be clinically osseointegrated. The specimens were processed for observation under light microscopy. Results: At low magnification, it was possible to observe that bone trabeculae were present around the implant. Areas of bone remodeling and haversian systems were present near the implant surface. Under polarized-light microscopy, it was possible to observe that in the coronal aspect of the thread, the lamellar bone showed lamellae that tended to run parallel to the implant surface, while in the inferior aspect of the thread, the bone lamellae ran perpendicular to the implant surface. Conclusions: Histologic data pertaining to these 3 immediately loaded implants, and retrieved after a 4-month loading period, show that immediate loading did not produce untoward effects on peri-implant bone healing. Bacterial Plaque Colonization Around Dental Implant Surfaces Implant Dentistry. 15(3):298-304, September 2006. Ugo Covani, DDS, MD; Simone Marconcini, DDS; Roberto Crespi, DDS, PhD; Antonio Barone, DDS, PhD Abstract: Purpose: To examine the distribution of bacteria into the internal and external surfaces of failed implants using histologic analysis. Materials and Methods: There were 10 failed pure titanium and 5 failed hydroxyapatite-coated titanium implants consecutively removed various years after their placement. Criteria for fixture removal were peri-implant radiolucency and clinical mobility. The mobile fixtures were retrieved with the patients under local anesthesia. Fixtures were removed maintaining the abutments with the aim to observe the bacterial infiltration at the level of abutment/implant interface and on the implant surface. Results: A thin radiolucent space was always present around all the failed implants. The abutments screws were tightly secured in all clinicalcases. The bacterial cells were composed of cocci and filaments, which were adherent to the implant surface with an orientation perpendicular to the long axis of the implant. All the specimens included in this study showed bacteria at the level of implant/abutment interface. Conclusions: Histologic analysis at the level of abutment/implant interface in 2-stage implants identified heavy bacterial colonization. These findings appear to support those studies showing bacteria penetration at the level of the micro-gap, which can legitimate the hypothesis that the micro-gap at the bone level could present a risk for bone loss caused by bacterial colonization. Measuring Mobility of 2 Dental Implant Fixtures of Different Configurations: An In Vitro Study Implant Dentistry. 15(3):290-297, September 2006. H Zeynep Ertugrul, DDS, PhD; Donald J. Pipko, DMD, MDS Abstract: Objectives: To our knowledge, it has not as yet been determined if mini-dental implants can be used as a long-term treatment method compared to endosseous standard root-form dental implant fixtures. This in vitro study investigates the stability of 2 different implants, 1 mini-dental implant and 1 endosseous standard root form dental implant, under lateral forces. Methods: There were 2 different screw-type dental implants with the O-ring/ball attachment prosthetic heads used. A mini-dental implant (Sendax MDI MAX; IMTEC, Corp., Ardmore, OK) 13 mm in length and 2.2 mm in diameter, and root form implant (Branemark; Nobel Biocare AB, Goteborg, Sweden) 13 mm in length and 4 mm in diameter. These implants were then embedded into a matrix mixture of pumice, two-fifths BaSO4 powder and one-fifth plaster. Parallel periapical radiographs were taken pretest and after lateral forces were applied. The implants were vi-brated using electric toothbrushes. They were attached to O-rings on the implants. Periapical radiographs were secured periodically every 5 minutes. The first discrepancy was observed at the 35th minute. Mobility and discrepancy values were recorded at the instances of 35th, 60th, 90th, and 120th minutes. Stability was measured and recorded using a manual stress and tension gauge. Radiographic discrepancy values were measured using a stereomicroscope. Results: The Branemark implant showed less mobility and discrepancy values than the mini-dental implant. The discrepancies were observed mostly at the cervical region of the 2 implants. Conclusions: According to the experimental results of this study, the Branemark implant was more stable than the mini- dental implant at the end of 2 minutes. Reconstruction of a Mandibular Critical-Sized Defect Using Iliac Graft in Rats Implant Dentistry. 15(3):282-289, September 2006. Rogerio S. Jorge, DDS, MS; Jacks Jorge Jr, DDS, PhD; João Gualberto C. Luz, DDS, MS, DSc Abstract: Objective: To evaluate, histologically and by optical densitometry of radiographs, the healing of a critical-sized defect in the rat mandible filled with iliac graft. Materials: The study was conducted on 25 adult Wistar rats. With the rats under general anesthesia, a bicortical critical-sized osseous defect was created in the right mandibular ramus and filled with autogenous iliac crest graft. The animals were divided into 5 groups, with 5 rats in each. They were sacrificed after 1, 7, and 14 days, and 1 and 3 months. The mandibles were removed, fixed in formalin, and radiographed. The right hemi-mandibles were decalcified, and sections were cut and stained with hematoxylin and eosin. Results: Initially, an acute inflammatory process was noted along the graft that was tightly fitted to the defect. Subsequently, intense bone neoformation from external corticals andin the inner spaces of the graft was observed, while medullar spaces were occupied by granulation tissue and osteoblasts. There was remodelation of the receptor site, with a decrease in the graft volume and medullary space, as well as cancellous bone replaced by compact bone. Later, the receptor site was similar to the normal mandible, and only devitalized remnants of corticals of the graft were found. Optical densitometry of radiographs revealed statistically significant differences between experimental and control sites. Conclusions: This experimental model is valuable in the study of bone healing. The study showed that autogenous iliac graft promoted healing of the critical-sized defect of the mandible with complete bony remodeling. Increasing the Width of Keratinized Mucosa Around Endosseous Implant Using Acellular Dermal Matrix Allograft Implant Dentistry. 15(3):275-281, September 2006. Jun-Beom Park, DDS, MSD Abstract: Objectives: To: (1) investigate the clinical efficacy of acellular dermal matrix allograft to achieve increased peri- implant keratinized mucosa around implants, and (2) evaluate the effect as to whether the increase of keratinized mucosa has a positive effect on oral hygiene. Materials and Methods: There were 10 male patients, ranging from 43 to 53 years of age, with attached gingiva <=2 mm on the buccal aspect included in this study. Acellular dermal matrix allograft was used to increase the keratinized mucosa on the buccal side. Results: The change of peri-implant pocket depth showed statistical differences among 3 measurements. The modified plaque index at 3 and 6 months showed statistical differences compared with the baseline measurements. The modified gingival index did not show any significant differences among all measurements. The width of peri-implant keratinized mucosa increased from a mean of 0.8 +/- 0.6 to 3.2 +/- 0.9 mm at 3 months and 2.2 +/- 0.6 mm at 6 months. Conclusions: It is concluded that the acellular dermal matrix allograft could be applied as a grafting material to increase the width of peri-implant keratinized mucosa. Its procedure appears to have some benefits for oral hygiene. Further randomized controlled trials over long periods of time are necessary to establish whether this procedure offers long-tem benefits to patients. Heterotopic Bone Formation Around Sintered Porous-Surfaced Ti-6Al-4V Implants Coated with Native Bone Morphogenetic Proteins Implant Dentistry. 15(3):265-274, September 2006. Ziv Simon, DMD, MSc; Douglas A. Deporter, DDS, PhD; Robert M. Pilliar, BA Sc, PhD; Cameron M. Clokie, DDS, PhD Abstract: Purpose: Coating endosseous dental implants with growth factors such as bone morphogenetic proteins (BMPs) may be one way to accelerate and/or enhance the quality of osseointegration. The purpose of this study was to investigate in the murine muscle pouch model whether sintered porous-surfaced titanium alloy implants coated with BMPs would lead to heterotopic bone formation around and within the implant surface geometry. Materials: Porous-surfaced dental implants were coated with partially purified native human BMPs, with or without a carrier of Poloxamer 407 (BASF Corp., Parsippany, NJ), placed in gelatin capsules and implanted into the hindquarter muscles of mice. Mice were euthanized after 28 days. Sections of retrieved specimens were subsequently prepared for morphometric analysis of bone formation using backscatter electron microscopic images. Results: Human BMPs, either with or without the carrier of Poloxamer 407, led to bone formation within and outside of the sintered porous implant surface. When the sintered implant surface region was subdivided into inner and outer halves, similar levels of bone ingrowth and contact were seen in the 2 halves. Evidence of bone formation to the depth of the solid implant core (i.e., the deepest level possible) also was seen. Discussion and Conclusions: Sintered porous-surfaced dental implants can be used as substrate for partially purified BMPs in the murine muscle pouch model. With the addition of these osteoinductive factors, the porous implant surface supported bone formation within the surface porosity provided, in some instances, all the way to the solid implant core. The addition of growth factors to a sintered porous surface may be an efficient method for altering locally the healing sequence and quality of bone associated with osseointegration of bone-interfacing implants. Finite Element Analysis of Different Bone Substitutes in the Bone Defects Around Dental Implants Implant Dentistry. 15(3):254-264, September 2006. Byung-Gon Kwon, DDS; Su-Gwan Kim, DDS, PhD Abstract: Purpose: To evaluate the distribution of stress and strain for the evaluation of implant and graft stability at each stage before stabilization of the graft is achieved after implantation was performed. Materials and Methods: Dembone (Pacific Coast Tissue Bank, Los Angeles, CA), Bio-Oss (Geistlich Pharma, Wolhusen, Switzerland), particulate dentin, and plaster of Paris were used to fill bone defects. The distribution of stress was compared in the mandible and maxilla, between vertical load and load applied at 30[degrees] angle, and according to time, with 3 different graft materials. Results: Stress occurred more when it was applied at an angle, rather than applied vertically. Stress was relatively high immediately after implantation, and particulate dentin-plaster of Paris showed larger mechanical properties and lower stress distribution overall. The largest stress distribution was shown when stress was applied at an angle when demineralized freeze-dried bone was used. The pattern of stress distribution was different according to differences in the mechanical properties of implants. Conclusion: Caution is needed not to apply stress at an angle immediately after implantation. Differences of stress were reduced with time as the implant became stabilized. Dentin Dysplasia Type I Treated with Onlay Bone Grafting, Sinus Augmentation, and Osseointegrated Implants. Implant Dentistry. 15(3):248-253, September 2006. Mario F. Muñoz-Guerra, MD, PhD; Luis Naval-Gías, MD, DMD, PhD; Verónica Escorial, MD; Jesús Sastre-Pérez, MD Abstract: Dentin dysplasia is a defect of dentin development that was classified by Shields as type I and type II. The teeth in dentin dysplasia type I are characterized by normal enamel and abnormal dentin in the crown and root. For that reason, this disorder is characterized by dental caries, early exfoliation of the teeth and, consequently, maxillomandibular bony atrophy. In this report, we present a case of a young girl affected by dentin dysplasia type I, treated witha combination of onlay bone grafting and a sinus lift technique to accomplish implant placement. This case showed that onlay autogenous grafting and a sinus lift technique are well-tested methods of bony augmentation and can be useful in patients with congenital dentin defects, such as dentin dysplasia. Prosthetic Rehabilitation of a Bone Defect with a Teeth-Implant Supported, Removable Partial Denture. Implant Dentistry. 15(3):241-247, September 2006. Renato de Freitas, PhD; Osvaldo Bazzan Kaizer, PhD; Marcelo Matida Hamata, MSc; Daniel Romeu Benchimol de Resende, MSC, PhD; Rosane de Oliveira Fortes Kaizer, DDS Abstract: The use of teeth-implant, mucosa-supported removable dentures for rehabilitation of partially edentulous patients involves highly complex biomechanical aspects. This type of prosthesis associates 3 kinds of support that react differently to the functional and parafunctional forces developed in the oral cavity. Although the construction of removable partial dentures may seem paradoxical when osseointegrated implants are placed, in some cases, this option is an excellent alternative to solve difficulties related to the anatomic, biologic, psychomotor, and financial conditions of the patient. This article reports on a case in which a teeth-implant, mucosa-supported removable partial denture was the option of choice for a patient with financial and anatomic limitations, having a large structural loss of the residual alveolar ridge caused by trauma by a gunshot injury at the mandible. The 5-year follow-up did not reveal any type of biomechanical or functional problem. Plastic Temporary Abutments with Provisional Restorations in Immediate Loading Procedures: A Clinical Report. Implant Dentistry. 15(3):236-240, September 2006. Eitan Mijiritsky, DMD Abstract: A provisional restoration in combination with an implant-retained restoration provides many of the same benefits as nonimplant-retained fixed restorations. Provisional restorations serve as a diagnostic tool to confirm esthetics, contours, accessibility for oral hygiene, and can be used to duplicate the definitive restoration. A provisional restoration allows for communication between the patient, dentist, and technician. The soft tissue around the implants can heal according to the contours of the provisional restoration. However, implant-retained treatment can require an extended period of osseointegration, and provisional treatment can be a challenge if a removable prosthesis is provided because adjustments of the denture may become necessary during healing. This article presents a case report that describes the simultaneous placement of implants with the connection of fixed provisional restorations to prefabricated plastic provisional abutments. Bone Marrow Aspiration: Technique, Grafts, and Reports Implant Dentistry. 15(3):229-235, September 2006. Dennis Smiler, DDS, MScD; Muna Soltan, DDS Abstract: This article describes a technique for obtaining adult stem cells from bone marrow aspirate. Case reports show how this procedure might replace the gold standard for bone grafts with the platinum standard of obtaining stem cells. The bone marrow aspirate and transplantation of adult stem cells within the resorbable) matrix and under the influence of soluble regulators have the potential for introducing the platinum standard for bone grafts. There are several advantages to using bone marrow aspirate. The technique is simple, a second surgical site is not needed, there is minimal postoperative morbidity, and adult stem cells populate the graft site with osteoblasts. Vertical Bone Augmentation: Where Are We Now? Implant Dentistry. 15(3):219-228, September 2006. Simon Bernstein, DDS; Jason Cooke, DDS; Paul Fotek, DMD; Hom-Lay Wang, DDS, MSD Abstract: As the prevalence of implants has increased, so has the challenge to augment the remaining osseous structure to house those implants. The biggest surgical challenge clinically is to augment lost bone vertically. The purpose of this article is to review currently available techniques for achieving greater vertical dimension before implant placement. A literature search was conducted using MEDLINE to find all articles published between 1970 and 2004 regarding vertical bone augmentation. Following the literature search, all articles were reviewed and summarized in this review article of vertical bone augmentation. The results of the research showed that guided-bone regeneration, monocortical onlay grafting, and distraction osteogenesis have the potential to be applied to augment deficient areas vertically. The expectations of dimensional gain and bone quality are unique to each technique, as well as the potential complications. Distraction osteogenesis has had the greatest potential for vertical gain, while guided-bone regeneration and monocortical onlay grafting achieve similar results. The choice of procedure is to be based upon the patient's existing anatomy, degree of vertical deficiency, and willingness to participate in treatment. Dental Endosseous Implants in Patients on Bisphosphonate Therapy Implant Dentistry. 15(3):212-218, September 2006. Crispian Scully, CBE, PhD, MD, MDS; Carlos Madrid, PhD, MD, DDS, MsS; Jose Bagan, PhD, MD, DDS Abstract: About a decade ago, bisphosphonates were introduced as an alternative to hormone replacement therapies for osteoporosis and to treat osteolytic tumors. More recently, it has became evident that the bisphosphonates used intravenously such as pamidronate (Aredia; Novartis Pharmaceuticals Corp., East Hanover, NJ) and zoledronate (Zometa; Novartis Pharmaceuticals Corp.), in particular, could lead to painful refractory bone exposure (sometimes termed osteochemonecrosis or osteonecrosis) in the jaws. Patients with osteonecrosis of the jaws usually present after dental treatment with oral signs and symptoms of painful, exposed, and necrotic bone, primarily of the mandible and, to a lesser extent, the maxilla. Although the precipitating event that produces this complication may be spontaneous, there is little doubt that oral surgery and endosseous implants can be responsible. Exodontia is the main precipitant. The present postulated mechanism of osteonecrosis of the jaws is that prolonged use of bisphosphonates may suppress bone turnover to the point that the repair function of physiologic microdamage of bone is abolished. Such a mechanism could presumably interfere with the healing process after implant placement. Although, to our knowledge, there is no evidence that bone disorders are a contraindication to implants, there is evidence that bisphosphonate therapy is a contraindication. Where possible, extractions should be avoided, and it is best to avoid all elective oral surgery in patients on bisphosphonates, including endosseous implant placement, or the treatment should be performed well before commencing bisphosphonates. If surgery is essential on a patient taking bisphosphonate therapy, the patient must be counseled about the risks.