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Background and objectives: Preservation of alveolar ridge contour following tooth extraction is important to allow for restoration with prosthetics and implants. Socket seal surgery was introduced more than two decades ago for preservation of the form, volume and bone quality of the postextraction ridge. The aim of this retrospective study was to assess the changes in alveolar ridge contour following socket seal surgery and to evaluate the survival of the soft tissue grafts sealing the extraction site. Materials and Methods: Digital images of the extraction sites treated with the socket seal surgery were obtained immediately after extraction and after a healing time of 6 months to measure the changes in the alveolar width. In addition, the sites were photographed 1 week postsurgery to evaluate the vitality of the soft tissue grafts. Results: The overall mean loss of buccal width following socket seal surgery was 5.3% (SD = 13.4%). The mean change in width at the incisor area (1.5% ± 13.1) was significantly lesser than those in the canine area (−17.0% ± 2.1, p < 0.01) or premolar area (−10.5% ± 11.2, p < 0.01). One-week post-surgery 69% of the grafts were vital, and 31% were partially vital. Complete necrosis of the grafts did not occur. Conclusions: Our results suggest that socket seal surgery has a beneficial effect on alveolar dimensional changes 6 months following tooth extraction and that the teeth that benefit mostly from socket seal surgery are incisors. [ABSTRACT FROM AUTHOR]

Purpose: The objective of this study was to compare the clinical and histologic peri-implant parameters of a nano-calcium phosphate (CaP)-coated dual acid-etched (DAE) implant (n = 7) to those of an uncoated DAE implant (n = 7). Materials and Methods: The study included seven dogs who received implants bilaterally in edentulous mandibular areas; in the right side, procedures were performed 8 months after procedures in the left mandible. Clinical parameters were measured prior to euthanasia (8 months after the second set of implants was placed), followed by histologic nondecalcified processing for morphometric evaluation. Bone-implant contact (BIC), crestal bone resorption (CBR), intrabony defect (IBD), and bone area fraction (BAF) were measured. Analysis of variance with repeated measures and a two-tailed Pearson correlation test were applied. Results: Probing depth, Bleeding Index, and keratinized mucosal height were stable in both groups; there was a significant improvement in probing depths with time (P = .014). Morphometric measurements showed BIC from 75% to 89% in both groups at 8 and 16 months. The nano-CaP-coated group (n-CaP) showed a significant increase in BIC over time when compared to the DAE group (P = .02). Crestal bone level was maintained in both groups with average resorption of 1.4 to 1.5 mm at the n-CaP implants and 1.1 to 1.2 mm at the DAE implants at 8 and 16 months, respectively. Mean IBD values were 0.88 to 1.18 mm at the n-CaP implants and 0.65 to 0.66 mm at the DAE implants at the respective periods. Conclusions: Within the limitations of this study, both the DAE and the n-CaP-surface implants showed successful osseointegration and functional soft and hard tissue adaptation. Except for the significant increase in BIC around the n-CaP implants over time, both showed similar clinical and histologic findings. [ABSTRACT FROM AUTHOR]

Purpose: The objective of this study was to histomorphometrically evaluate the synthetic peptide analog P-15 bound to anorganic bovine mineral (Pepgen/P15) in critical-size defects in the rat calvaria. Materials and Methods: A 5-mm-diameter critical-size defect was prepared in 48 rat skulls and divided into 4 equal groups: Pepgen/P15 particles covered by a membrane, Pepgen/P15 particles uncovered, nongrafted membrane-protected sites, and nongrafted uncovered control sites. At 12 weeks, histomorphometric measurements were made of the percentage area of newly formed bone and residual particles, the length of internal and external bone bridging, and linearly, the regenerated marginal and central total tissue augmentation height. Results: Nongrafted, membrane-protected sites gained 60.6% of newly formed bone, followed by 50.6% and 44.2% (P < .05 versus membrane only) at the grafted covered and uncovered sites, respectively. All experimental sites contained significantly (P < .005) more bone than did control sites (19.9%). In both types of grafted sites, the percentage area of Pepgen/P15 particles was similar. Mean internal and external length of bone bridging at nongrafted membrane-protected sites (76.7% and 71.2%, respectively) was significantly greater (P < .005) than that of the grafted covered (43.95% and 51.8%, respectively), grafted uncovered (28.7% and 23.9%, respectively), and control (28% and 25.5%, respectively) groups, except for internal bone bridging in the grafted covered sites. Regenerated marginal and central augmentation heights (0.92 mm and 1.02 mm, respectively) were greatest in the grafted covered group, followed by the nongrafted membrane-protected (0.88 mm and 0.51 mm, respectively), and grafted uncovered (0.89 mm and 0.12 mm, respectively) groups, all of which were significantly greater (P < .001) than the control group (0.63 mm and 0.04 mm, respectively). Conclusion: While anorganic bovine mineral/cell-binding peptide contributes in volume, membrane application significantly increases the amount of bone regeneration. [ABSTRACT FROM AUTHOR]

Purpose: An inorganic xenograft (inorganic bovine bone [IBB]) and a porous alloplast (β-tricalcium phosphate [β-TCP]) material were compared at different healing periods in experimental bone defects in dogs. Materials and Methods: Six round defects, 5 × 4 mm, were made on the lateral bony mandibular angle in 8 dogs at different times. Two defects were randomly filled with IBB, 2 with β-TCP, and 2 were left to blood clot. A bi-layer collagen membrane covered 1 defect of each type. Four specimens per treatment group were obtained for each treatment group at 3, 6, 12, and 24 months postoperatively. Morphometric analysis of decalcified (Donath technique) histologic slides was conducted using the measured areas of regenerated bone, grafted particles, and remaining concavity. Results: In IBB sites, complete bone healing was evident at 12 and 24 months, but grafted particles dominated the sites. In β-TCP sites, only particle remnants remained at 12 months. At 24 months, particles had completely resorbed in both membrane-protected (MP) and uncovered (UC) defects. Data were combined for final analysis since there were no statistically significant differences within each graft material group (MP or UC). Mean bone area fraction increased from 3 to 24 months at all sites. In bone area fraction a statistically significant difference was found between 3 and 6 months in the IBB and β-TCP groups. IBB sites also showed such significance between 6 and 12 months. A statistically significant difference was found between MP ungrafted sites (42.9%) vs IBB (24.7%) and vs the control (24.8%) at 3 months. At 6 months, β-TCP bone area fraction (68.8%) was significantly greater than IBB (47.9%) and control (37.5%) sites. At 12 months, β-TCP bone area fraction (79.0%) was significantly greater than the control (42.5%). At 24 months, β-TCP bone area fraction (86.5%) was significantly greater than IBB (55.6%) sites. Mean particle area fraction of β-TCP sites decreased gradually until complete resorption at 24 months. IBB sites showed a significant decrease only between 3 (38.7%) and 6(29.4%) months. Discussion and Conclusion: Complete bone healing was established in all grafted defects. IBB and β-TCP are both excellent biocompatible materials. However, at 24 months β-TCP particles were completely resorbed, whereas IBB particles still occupied a remarkable area fraction without significant resorption beyond 6 months. [ABSTRACT FROM AUTHOR]

To evaluate the possibility of regenerating bone around endosseous dental implants, 3t implants were placed into postextraction sockets or other bony defects, and human demineralized freeze-dried cortical bone powder (DFDB) mixed with tetracycline was packed around the exposed parts. Implants were covered with expanded polytetrafluoroethylene (e-PTFE) membranes for 4 to 6 months until abutment connection, unless the membranes were prematurely exposed and had to be removed. Bone biopsies from nonsupporting regenerated bone were taken from some of the patients and examined histologically. Whenever complete coverage was maintained throughout the healing period (4 to 6 months), complete bone regeneration resulted. Early membrane removal mainly resulted in partial bone regeneration. Histologically, regenerated bone consisted of particles of devitalized bone in contact with newly formed woven or lamellar bone with some connective tissue around them. Osteogenic activity was even present 1 year post-grafting. Thus, DFDB is capable of promoting bone formation around dental implants if complete flap coverage and the membrane presence can be maintained throughout the healing phase. [ABSTRACT FROM AUTHOR]