Ridge preservation following tooth extraction using bovine xenograft compared with porcine xenograft: A randomized controlled clinical trial

Background: The primary purpose of this study was to histologically determine if there is a significant difference in new bone formation, residual graft material, and connective tissue/other when ridge preservation is accomplished using a bovine versus a porcine xenograft. Methods: Forty-four patients needing a single rooted tooth extraction and ridge preservation in preparation for dental implant placement were recruited in the study. After minimally traumatic tooth extraction, alveolar ridge dimensions were measured using a custom-fabricated acrylic stent. Patients were then randomized 1:1 to receive ridge preservation using either bovine or porcine xenograft material. A trimmed dense polytetrafluoroethylene (d-PTFE) membrane was overlaid on the graft material, the mucoperiosteal flaps were replaced, and the surgical site was sutured. After 18 to 20 weeks of wound healing, sites were surgically re-entered, ridge dimensions were again measured using the previously fabricated acrylic stents and a bone core sample of the grafted site was harvested for histomorphometric analysis. Results: Thirty eight of the 44 enrolled patients completed the study, 17 from the bovine group and 21 from the porcine group. Histologically, there were no statistically significant differences between the groups for mean percentage of vital bone formation (bovine = 36.21%, porcine = 31.27%, P = 0.49), residual graft material (bovine = 20.47%, porcine = 19.52%, P = 0.82) and connective tissue/other (bovine = 43.32%, porcine = 49.21%, P = 0.19). For secondary outcomes, there were no significant differences between the groups for mean change in buccal ridge height, lingual ridge height, and ridge width. However, a higher number of patients in the porcine group had additional grafting at the time of implant placement, either because of thin buccal plate or failure of implant stability. Conclusion: The findings suggest that ridge preservation with porcine xenograft results in comparable histomorphometric outcomes and dimensional stability with bovine xenograft.