Ridge Preservation Following Tooth Extraction Using Two Mineralized Cancellous Bone Allografts

The study is designed to examine histologic wound healing following ridge preservation using cancellous bone allograft that has been prepared either by freeze-drying (FDBA) or by a solvent-based processing method (PUROS). This entire protocol involves procedures that are standard care. All materials are FDA-approved materials being used in an FDA-approved manner. The test group subjects will have extraction sockets grafted with a cancellous non-freeze-dried bone allograft (called PUROS graft). This test group will be compared to an active control group using cancellous freeze-dried bone allograft (called FDBA). The null hypothesis is that there will be no significant difference in formation of new vital bone between treatment groups (primary outcome). Each subject will provide a single non-molar tooth site for study treatment. After tooth extraction, the graft material will be placed and covered by a resorbable collagen membrane. Following 3 months of healing, the dental implant will be place, at which time a core of bone will be removed from the site as part of the preparation for the implant. The core biopsy will then be evaluated for the primary histologic outcome of % vital bone formation and secondary histologic outcome of % residual graft material.