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Objectives: The aim of this study is to evaluate long‐term in vivo stability of dental implants stabilized at time of placement in oversized osteotomies with a novel, self‐setting, mineral–organic bone adhesive. Materials/Methods: Canine (26) mandibular teeth were removed, and three oversized osteotomies prepared bilaterally. Implants were placed with either adhesive, particulate xenograft, or with blood clot filling the implant/osteotomy gaps. Removal torque and histology were assessed. Results: The adhesive provided significant and clinically relevant immediate implant stability of 22.2 N‐cm (95% CI 5.3; 39.0), which continued throughout the early postoperative course and persisted through the nine‐ (155 N‐cm 95% CI 113; 197) and 12‐month (171 N‐cm 95% CI 134.2; 209.4) time points. This is in comparison with the blood clot of 1.4 N‐cm (95% CI 0.7; 2.1), 128.6 N‐cm (95% CI 66.8; 190.4), and 140.7 N‐cm (95% CI 78.8; 202.5) and particulate xenograft, 1.3 N‐cm (95% CI 0.6; 2.0), 132.1 N‐cm (95% CI 94.5; 169.7), and 101.5 (95% CI 59.5; 143.5), respectively. Histological examination shows the adhesive establishes intimate contact with the implant and bony walls and is replaced with new bone without compromising stability. Soft tissue does not penetrate the adhesive, and marginal bone/biomaterial level is maintained. Control sites filled with xenograft or blood clot heal with reduced bone levels, and in some cases, xenograft particles were encapsulated in connective tissue. Conclusions: Implants placed in oversized osteotomies and lacking primary stability can be stabilized at placement with a novel, highly osteoconductive, and resorbable adhesive. Gradual replacement of the biomaterial allows osseointegration without loss of stability through 12 months of follow‐up. This novel adhesive has the potential to stabilize implants placed in sites with inadequate bony support. [ABSTRACT FROM AUTHOR]

Objectives: The purpose of this prospective, single‐center randomized pilot study was to histologically evaluate and compare vital bone development in premolar and molar‐extraction sites grafted with two different bovine‐derived xenografts. The secondary outcome of interest was implant survival in the grafted sites. Materials and Methods: Adult patients in need of at least two tooth extractions were enrolled. A paired design was used; each patient received at least one of each type of graft at different sites. Each extraction site was randomized to one of two xenograft treatment groups. A resorbable membrane was always placed, and primary intention soft tissue closure was achieved. Four months later, implants were placed and a trephine drill was used to remove bone cores for histologic and histomorphometric analysis. Results: Sixteen patients with 40 extraction sites were enrolled; 20 sites were grafted with one type of xenograft and 20 with another. Mean patient age was 53.5 years, and 65% of patients were male. Evaluation of bone core samples taken from grafted sites showed no significant difference in the mean value of percentage of new bone formation between the different grafted sites (33.4% and 32.4%, p =.76). Cumulative implant survival was 97.5% at the 24‐month follow‐up visit. Conclusion: Within the limitations of this pilot study, no statistically significant differences in new bone growth between sites grafted with two different types of xenograft were found. Both graft materials promoted the formation of new bone and provided osseous support for implant placement after socket grafting. [ABSTRACT FROM AUTHOR]

Background Implant dentistry in the posterior maxilla often requires bone augmentation. The gold standard, autogenous bone graft, requires additional surgery with associated morbidity, while bone biomaterials may not support relevant bone formation. Recombinant human bone morphogenetic protein-2 ( rhBMP-2) in an absorbable collagen sponge ( ACS), however, induces significant, clinically relevant bone formation in several settings including the maxillary sinus floor. Objective The objective of this study was to compare local bone formation and osseointegration following maxillary sinus augmentation using rhBMP-2/ ACS or a particulate autogenous cancellous bone graft obtained from the iliac crest in conjunction with immediate placement of dental implants. Materials and methods Bilateral sinus augmentation using an extraoral approach including rhBMP-2 (0.43 mg/ml)/ACS or the autogenous bone graft, alternated between left and right sinus cavities in five adult male Yucatan mini-pigs, was performed. Two 12-mm dental implants were inserted into the sinus wall protruding approximately 8 mm into the sinus cavity. Surgical sites were closed and sutured in layers; block biopsies collected for histometric analysis at 8 weeks. Results rhBMP-2/ ACS induced bone of significantly greater and consistent quality compared with the iliac crest autogenous bone graft; bone density averaging 51.9 ± 3.0% vs. 32.9 ± 2.5% ( P = 0.01). However, there were only numerical differences in augmented bone height (9.3 ± 0.5 vs. 8.6 ± 0.7 mm) and bone-implant contact (37.4 ± 3.0% vs. 30.7 ± 5.9%) between treatments. Conclusion rhBMP-2/ ACS induces bone of superior quality compared with an iliac crest particulate autogenous cancellous bone graft when used for maxillary sinus augmentation, and should perhaps be considered the new standard for this indication. [ABSTRACT FROM AUTHOR]