Effect of allogeneic freeze-dried demineralized bone matrix on regeneration of alveolar bone and periodontal attachment in dogs.

This split-mouth study was designed to evaluate regeneration of alveolar bone and periodontal attachment following implantation of allogeneic, freeze-dried, demineralized bone matrix (DBM). Buccal fenestration defects (6x4 mm) were created on the maxillary canine teeth in 6 beagle dogs. DBM was implanted into one randomly selected defect in each animal. The contralateral defect served as surgical control. Tissue blocks were harvested following a 4-week healing interval and prepared for histometric analysis. DBM was discernible in all implanted defects with limited evidence of bone metabolic activity. The DBM particles appeared invested within a dense connective tissue, often in close contact to the instrumented root. Fenestration defect height averaged 3.8+/-0.1 and 3.7+/-0.3 mm, total bone regeneration 0.9+/-0.9 and 0.4+/-1.2 mm, and total cementum regeneration 2.3+/-1.5 and 0.6+/-0.7 mm for DBM and control defects, respectively. Differences with regards to cementum regeneration were statistically significant (p=0.03). In summary, the results of this study suggest that DBM implants may enhance cementum regeneration in this defect model, and that they have no apparent effect on alveolar bone regeneration. Enhanced cementum regeneration may be possibly be explained by provisions for guided tissue regeneration from the implant suppressing a significant influence of the gingival connective tissue on the healing process. Moreover, a 4-week healing interval appears insufficient for turnover of DBM.