[Ectopic bone induction in recombinant human bone morphogenetic protein-2 (rhBMP-2) combined with biphasic calcium phosphate (BCP)].

The purpose of this study was to investigate the efficacy of BCP granules combined with rhBMP-2 for ectopic bone formation in rats. BCP granules were used as a carrier for rhBMP-2. The rhBMP-2 was adsorbed to BCP granules under the reduction of pressure. Twenty Wistar rats were used for this experiment and were divided into 4 groups according to the concentration (0,2,10,50 micrograms/700 microliters) of rhBMP-2 implanted in each rat. The BMP and BCP complex was implanted under the dorsal skin of the rats. Three weeks after the implantation, the rats were sacrificed. The experimental sites were immediately dissected and histological sections were prepared. In the 50 micrograms group, new bone formation was observed in all rats, while bone tissue was not found in the 2 micrograms and 0 microgram groups. These results indicated that BCP combined with rhBMP-2 could effectively induce ectopic bone formation. It was suggested that BCP granules alone could be applicable as a carrier for rhBMP-2 in order to induce new bone formation.