Abstract
In therapeutic bone repairs, autologous bone grafts, conventional or vascularized allografts, and biocompatible artificial bone substitutes all have their shortcomings. Tissue engineering may be an alternative for cranial bone repair. Titanium (Ti) and its alloys are widely used in many clinical devices because of perfect biocompatibility, highly corrosion resistance and ideal physical properties. An important progress in treating bone defects has been the introduction of bone morphogenetic proteins (BMPs), specifically BMP-2. The proteins induce osteogenic cell differentiation in vitro, as well as bone defect healing in vivo. In this study, we fabricated the titanium plate with dioxide creating by microarc oxidation (MAO) and then electronic deposition of Ca.P that can carrier recombinant human bone morphogenetic protein-2 (rhBMP-2) to enhance osteogenesis in vitro and bone formation in vivo. The rhBMP-2 was controlled released from MAO-Ca.P-rhBMP2 implant was maintain within 35days longer than Ti without MAO modification group and without CaP electronic deposition group. In addition, the in vitro results revealed that the bioactivity of rhBMP-2 released from MAO-Ca.P-rhBMP2 implant with an ideal therapeutic dose was well maintained. In vivo, the critical-sized defect (20-mm diameter) of New Zealand White rabbits was used to experiment. We concluded that sustained controlled-release of rhBMP-2 above a therapeutic dose could induce osseointegration between the implant and surrounding bone the rate of bone formation into the implant and produce neovascularization. Our study combined the concept of osteoconductive and osteoinductive to do the bone tissue regeneration.
