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Purpose: The aim of this study was to evaluate the performance of implants placed for 5 years in grafted vs nongrafted sinuses in relation to crown-to-implant ratio. The measurements of crown and implant lengths took into account changes in both endo-sinus and crestal bone levels over 5 years. Materials and Methods: Enrolled patients required one or two implants in at least one sinus and presented a residual bone height of posterior maxilla ≤ 4 mm. Individual sinuses were randomly allocated either to be grafted or not before surgery. Implants of 8 mm in length were placed using osteotome sinus floor elevation (OSFE). After 10 weeks of healing, they were loaded functionally using definitive single crowns. Radiographic measurements were made on periapical radiographs taken at surgery, prosthetic steps, and 5 years. The implant length was measured between the most apical and coronal contact of bone and implant, and the crown length was measured between the most occlusal point of the crown and the crestal bone. Data were analyzed using mixed linear models. Results: Twenty implants were placed in grafted sinuses and 17 in native bone (12 patients). One of the 35 restored implants failed. Immediately after surgery, the mean lengths of the implants placed in grafted and nongrafted sites were 2.4 ± 0.8 and 2.7 ± 0.9 mm, respectively (P = .351). At loading, the mean crown-to-implant ratios were 3.8 ± 0.8 and 4.6 ± 2.0 (P = .033), respectively, whereas at 5 years, they were 2.0 ± 0.8 and 2.1 ± 0.4, respectively (P = .341). Conclusion: The use of grafting material is not necessary to restore posterior maxilla ≤ 4 mm with OSFE and simultaneous implant placement. Over 5 years, all restored implants but one were functional. Despite unfavorable conditions in terms of initial bone anchorage and height of single crown restoration, a high initial crown-to-implant ratio did not compromise the long-term survival of implants placed in grafted or nongrafted sinuses. [ABSTRACT FROM AUTHOR]

Purpose: Ridge preservation limits dimensional changes after tooth extraction. However, it is still unclear if using a membrane may be advantageous over a collagen wound dressing. Therefore, the goal of this report was to evaluate the outcomes of ridge preservation using freeze-dried bone allograft with a collagen wound dressing. Materials and Methods: This study included 21 patients who had one molar extracted, and the site received ridge preservation using freeze-dried bone allograft and a collagen wound dressing (test 2 group). Patients had two standardized cone beam computed tomography (CBCT) scans, taken within 72 hours and 3 months after extraction, to measure changes in ridge height and width, and buccal and lingual plate thicknesses. Changes in keratinized tissue width were recorded. Three-arm analyses were performed using historic data from a previous randomized controlled trial by the same study group, in which 20 molar sites received a collagen wound dressing alone (control) and 20 received ridge preservation with freezedried bone allograft and a dense polytetrafluoroethylene membrane (test 1) using the same methodology. Results: There was a statistically significant difference in mean buccal ridge height changes between the control group (2.6 ± 2.06 mm) and test 2 group (1.55 ± 0.93 mm) but no difference in ridge and keratinized tissue width changes between groups. No correlation was found between buccal plate thickness and ridge width change. Conclusion: Freeze-dried bone allograft with collagen wound dressing as a barrier was used successfully for ridge preservation in intact molar extraction sites (< 50% bone loss) and can be considered as a treatment alternative to freeze-dried bone allograft with a dense polytetrafluoroethylene membrane. [ABSTRACT FROM AUTHOR]

Background: To determine if there is a difference in the amount of shrinkage during healing of free soft tissue autografts (FSTAs) using different surgical techniques-suturing the vestibular flap margin apically to the base of the recipient bed versus leaving the flap margin free and unsutured.Methods: Twenty-eight patients with mucogingival defects requiring FSTAs were recruited and enrolled in the study. Patients were randomized into test and control groups (14 per group) and received ≥1 FSTAs on non-molar mandibular teeth. In the test group the mucosal flap margin was sutured apically to the periosteum at the base of the graft; whereas, the mucosal flap margin in the control group was left free. Graft dimensional measurements were taken at time of surgery, then at 1, 3, and 6 months post-surgery.Results: Thirty-five grafts were performed (15 test, 20 control). All FSTAs experienced vertical shrinkage after 6 months, but there was no significant difference (P = 0.51) in the mean amount of shrinkage after 6 months between the test (23.20% ± 20.88%) and control (21.10% ± 21.88%) groups. There was significantly greater horizontal shrinkage in the test (loss of 7.59% ± 10.20%) compared with the control (small gain of 0.32% ± 4.20%) group (P = 0.01).Conclusions: The findings suggest that there is similar vertical shrinkage when performing FSTA surgery when the mucosal flap margin is left free and unsutured when compared with leaving the flap margin free. [ABSTRACT FROM AUTHOR]

Background: Little evidence is available regarding the benefit of ridge preservation (RP) at molar sites. The primary objective of this three-arm cohort study was to histologically compare the healing outcome between natural healing after molar tooth extraction and two different techniques of RP using freeze-dried bone allograft (FDBA) and a nonresorbable dense polytetrafluoroethylene (dPTFE) membrane, or an absorbable collagen sponge as a barrier.Methods: Seventy-nine patients requiring extraction and delayed implant placement were placed into three groups: extraction alone (control); ridge preserved using FDBA; and either dPTFE (Test1) or collagen sponge (Test2). Bone cores were harvested from implant osteotomies at ≈3 months after extraction for histomorphometric analysis to determine the percentage of vital bone, residual graft, and connective or other tissue. Ridge dimension changes were also evaluated radiographically (cone-beam computed tomography).Results: The percentage of vital bone was significantly greater in control group compared with Test1 but was not statistically different among other groups. Test2 showed significantly less connective or other tissue than control and Test1. The percentage of residual graft was significantly lower in Test1 compared with Test2. There was no significant correlation between the percentage of vital bone or residual graft and the following parameters: healing time, patient age, gender, buccal plate thickness, or radiographic changes in ridge dimensions.Conclusion: RP at molar sites using FDBA and an absorbable collagen sponge may be a sufficient and economic way to preserve the ridge dimension without interfering with the amount of new bone formation. [ABSTRACT FROM AUTHOR]

Dental implant-related abstracts are presented including the abstracts "Accuracy of digital versus conventional implant impressions" by S.J. Lee and others, "Accuracy of digital impressions of multiple dental implants: An in vitro study" by S. Vandeweghe and others, and "A novel method to evaluate precision of optical implant impressions with commercial scan bodies--An experimental approach" by T. Flügge and others.

The article presents abstracts concerning dental implants including the articles "Short implants versus longer implants in vertically augmented posterior mandibles: A randomized controlled trial with 5-year after loading follow-up" by P. Felice and others, "Success rate of short dental implants supporting single crowns and fixed bridges" by H. Malmstrom and others, and "Denture-related biomechanical factors for fixed partial dentures retained on short dental implants" by B. Pommer and others.

The article presents several abstracts on dental implants, including one by M. Esposito, M. G. Grusovin, H. Maghaireh et al. on dental implant loading, one by B. R. Chrcanovic, T. Albrektsson, and A. Wennerberg on functional loading and dental implant failure rates and one by F. Bassi, A. B. Carr, T. L. Chang et al. on the longevity of dental implants.

Purpose: The purpose of this experimental study was to analyze radiographically in a dog model how different implant-abutment interface configurations influence alveolar crestal bone changes. Materials and Methods: Six different experimental implant-abutment connections were evaluated in six mixed-breed dogs. The following parameters were tested: absence of microgap, microgap proximal to bone crest, and microgap distant from bone crest. In addition, two different cervical abutment profiles, one straight and one featuring a supracrestal concavity, were evaluated. Implants were based on a cylindrical full-body screw design and made from cold-worked grade IV commercially pure titanium. The diameter (at thread tips) measured 4.1 mm, whereas the inner diameter was 3.5 mm. Standardized periapical digital radiographs were obtained for comparative analysis at baseline and at 3, 4, 5, 6, 7, 8, and 9 months after implant placement. Radiographs were randomized and calibrated for linear measurements. For statistical analysis, mixed-model repeated-measures analysis of variance was used. Results: All implants integrated successfully and remained stable during the entire period of the study. Radiographically, when comparing groups with straight profiles, crestal bone remodeling in group C (one-piece design) was significantly less than in group A (matching diameters) and B (nonmatching diameters). In fact, implant group C showed the least crestal bone remodeling of all groups. When comparing groups with a concave profile but different microgap configurations, all three designs demonstrated bone loss with no significant differences among the three groups. Conclusion: A nonsubmerged one-piece implant design demonstrated the least amount of bone remodeling of all groups. Implant-abutment connections with a concave profile established crestal bone levels immediately apical to the concavity regardless of the microgap variable. [ABSTRACT FROM AUTHOR]

The author discusses the use of antibiotics after dental implant procedures. He mentions the possibility of infections at the site of the implant, the patterns of prescribing antibiotics as a prophylactic measure, and the issue of how useful such prescriptions are.

The article presents abstracts on medical topics, which include stress analysis methods to evaluate the biomechanics of oral rehabilitation with implants, disocclusion in complete dentures supported by implants, and three-dimensional finite element analysis for overdenture attachments.

The article presents several abstracts related to implant dentistry, including one on the immediate implant placement of mandibular molars, one on immediate postextraction implant placement with immediate loading in the maxilla and one on the immediate provisionalization of single Osseospeed implants.

The article presents several abstracts related to platform switching and dental science, including one on platform switching for marginal bone preservation around dental implants, one on platform-switched implants observed from 1992 to 2006 and one on platform switching and marginal bone-level alterations.

Purpose: The aim of the present study was to report the radiographical prevalence of overhanging fillings in a group of Swiss Army recruits in 2006 and to relate the dimensions of the overhangs to clinical parameters.Materials and Methods: A total of 626 Swiss Army recruits were examined for their periodontal conditions, prevalence of caries, and stomatological and functional aspects of the masticatory system and halitosis. In particular, the present report deals with the presence or the absence of fillings, the presence or the absence of overhangs and their relation to clinical and radiographic parameters.Results: A total of 16,198 interdental sites were evaluated on bitewing radiographs. Of these sites, 15,516 (95.8%) were sound and 682 (4.2%) were filled. Amalgam restorations were found in 94.1% and resin composite fillings in 5.9% of the sites. Of these 682 sites, 96 (14.1%) yielded overhanging margins of various sizes. This low prevalence of fillings represents not only a substantial reduction when compared with a similar Swiss Army study (Lang et al, 1988), but also an improvement in the quality of dental care delivery to young Swiss males. Plaque Index and Gingival Index increased statistically significantly with the presence of fillings, when compared with healthy non-filled sites. Clinical parameters that were significantly associated with the presence of overhangs included clinical attachment loss. Moreover, between 1985 and 2006 the prevalence of fillings was significantly reduced from 20.0% to 4.2% of all surfaces. Furthermore, the marginal fit of the fillings improved from 33.0% with overhangs to 14.1%.Conclusions: A significant improvement was observed in the periodontal and dental conditions of young Swiss males that was shown to have taken place within the previous two decades. From 1985 to 2006, the prevalence of fillings was reduced fourfold and that of overhanging margins twofold, documenting an improvement in the quality of restorative dentistry. [ABSTRACT FROM AUTHOR]

Purpose: The aim of this review was to evaluate a history of treated periodontitis and smoking, both alone and combined, as risk factors for adverse dental implant outcomes. Materials and Methods: A literature search of MEDLINE (Ovid) and EMBASE from January 1, 1966, to June 30, 2008, was performed, and the outcome variables implant survival, implant success, occurrence of peri-implantitis and marginal bone loss were evaluated. Results: Considerable heterogeneity in study design was found, and few studies accounted for confounding variables. For patients with a history of treated periodontitis, the majority of studies reported implant survival rates > 90%. Three cohort studies showed a higher risk of peri-implantitis in patients with a history of treated periodontitis compared with those without a history of periodontitis (reported odds ratios from 3.1 to 4.7). In three of four systematic reviews, smoking was found to be a significant risk for adverse implant outcome. While the majority of studies reported implant survival rates ranging from 80% to 96% in smokers, most studies found statistically significantly lower survival rates than for nonsmokers. Conclusions: There is an increased risk of peri-implantitis in smokers compared with nonsmokers (reported odds ratios from 3.6 to 4.6). The combination of a history of treated periodontitis and smoking increases the risk of implant failure and peri-implant bone loss. [ABSTRACT FROM AUTHOR]

This review presents the various techniques, the indications and contraindications for surgical lengthening of the clinical crown. Based on the concept of biologic width of the dento-gingival complex, the aim of surgical modifications in this region is to create a distance of approximately 3 mm between the foreseeable marginal area of a reconstruction and the crest of the alveolar bone. Studies on wound healing suggest that stability of the soft tissues following such surgical procedures is obtained after a healing period of 6 months. In order to obtain optimal aesthetic treatment outcomes of restorations, the duration of the healing period should be respected. [ABSTRACT FROM AUTHOR]

The article presents abstracts on oral implants and radiotherapy-related topics including "Survival of dental implants in patients with oral cancer treated by surgery and radiotherapy: A retrospective study" by G. Pompa and others, "Overdentures on primary mandibular implants in patients with oral cancer: A follow-up study over 14 years" by A. Korfage and others, and "Implant-based rehabilitation in oncology patients can be performed with high long-term success" by S.A. Hessling and others.

Background: To date, limited evidence is available specifically evaluating ridge preservation (RP) and implant placement in molar sites. The primary aim of this study is to radiographically compare alveolar ridge changes with and without RP with cone-beam computed tomography (CBCT).Methods: This parallel, two-arm randomized clinical trial included 40 patients evenly distributed between two treatment groups. After molar extraction, sites were allowed to heal naturally or received RP with freeze-dried bone allograft covered by a non-resorbable dense polytetrafluoroethylene membrane. CBCT scans were taken immediately and 3 months postextraction, and then a dental implant was placed. Width and height measurements were made radiographically.Results: Significantly greater loss in alveolar ridge height was found in molar sites allowed to heal without RP on the buccal aspect of the socket (RP: -1.12 ± 1.60 mm versus no RP: -2.60 ± 2.06 mm, P = 0.01). No significant difference in ridge width loss was found between groups. Two-thirds ridge width reduction was experienced on the buccal aspect in sites without RP, but width loss was evenly distributed between buccal and lingual aspects when RP was performed. Bone grafting at time of placement was required in 25% of implants in the group without RP versus 10% of implants in the RP group.Conclusions: In molar extraction sites without RP, significantly more reduction in ridge height occurred, and the majority of ridge width loss was localized to the buccal aspect. When RP was performed, ridge width loss was not significantly decreased, but the loss was evenly distributed between facial and lingual aspects of the extraction site. [ABSTRACT FROM AUTHOR]