A novel growth factor bioavailability-enhanced allograft for use in craniomaxillofacial bone regeneration.

INTRODUCTION: Regeneration of bone in challenging clinical environments requires use of a bone graft substitute that is both osteoregenerative and osteoconductive. Several bone grafts claim osteoregenerative potential, including allogeneic protein-enhanced (OsteoAMP and OsteoFactor), cell-binding peptide-enhanced (i-Factor), recombinant bone morphogenetic protein 2 (BMP-2) containing (INFUSE), or cellular allografts (ViviGen and Trinity). Recently, a novel growth factor bioavailability-enhanced allograft (Natural Matrix Protein®, NMP), was developed that similarly claims osteoregenerative potential. This article evaluates NMP and compares it to other bone grafts. METHODS: The release of BMP-7 into PBS + Tween over 14 days from demineralized bone matrix (DBM) and NMP prepared from the same donors was measured by ELISA. The osteoinductive potential of NMP mixed with different amounts of inactive DBM was assessed in the athymic rat muscle pouch by microCT and histomorphometry. A second muscle pouch study evaluated the osteoinductive and osteogenic properties of OsteoAMP, OsteoFactor, i-Factor, ViviGen, Trinity, and INFUSE compared to NMP. The clinical potential of NMP to regenerate a severely atrophic maxilla and support dental implant placement was evaluated in two cases. RESULTS: NMP released significantly more BMP-7 than DBM over 14 days. NMP-iDBM mixtures were osteoinductive when the mixture contained 100%, 75%, and 50% NMP. MicroCT analysis of OsteoAMP, i-Factor, ViviGen, and Trinity showed they all contained mineralized tissue prior to implantation, confounding microCT evaluation of the recovered implants. Histological analysis showed that OsteoAMP, OsteoFactor, and i-Factor failed to form bone in vivo. The cellular allografts produced new bone inconsistently, while INFUSE and NMP consistently formed bone. The clinical cases showed that the use of NMP resulted in bone regeneration of sufficient volume and quality to support placement and function of dental implants. CONCLUSION: NMP is osteoinductive in vivo and can support bone regeneration clinically.