A preliminary study of the osteogenic potential of a biodegradable alloplastic-osteoinductive alloimplant.

A biodegradable copolymer of polylactide-polyglycolide was combined with allogeneic demineralized freeze-dried bone (DFDB) and implanted into 15-mm diameter defects in the calvaria of 26 New Zealand White rabbits. Similar defects were created in the calvaria of another 26 rabbits. These animals served as controls and did not receive copolymer implants. Upon sacrifice, both the implants and the controls were evaluated clinically, roentgenographically, and histomorphometrically using a Zeiss Image Analysis System (Videoplan, version 4.1). Both controls and implants were evaluated in groups at four, eight, 12, 16, 20, and 24 weeks. When compared with the control defects, the copolymer-DFDB implants displayed a significantly greater volume of trabecular bone. Three of the 15-mm diameter defects displayed evidence of complete osseous bridging at eight weeks. No adverse host-tissue responses were observed histologically in any of the implant specimens.