Ultra microstructure and histological properties in vivo of excellent composition of decalcified bone matrix impregnated calcium phosphate cement with recombinant human bone morphogenetic protein-2 in periods / 解放军医学杂志

ABSTRACT

Objective To analyze the ultra microstructure and histological properties of implanted composites of decalcified bone matrix (DBM) impregnated calcium phosphate cement (CPC) with recombinant human bone morphogenetic protein-2 (rhBMP-2) in bone defect, and evaluate the osteoplastic efficiency of this composites. Methods The rabbit DBM was prepared beforehand. The composites of DBM impregnated CPC with rhBMP-2 was made at 0.2 proportion of DBM. The rabbit's bone defect of femur condyle was filled with implantation of the composites (group A, n=12) or CPC (group B, n=12) or bone cement (group C, n=12). Animals were sacrificed at 6, 12, or 24 weeks after operation, and the implants were examined by histological technique and scanning electron microscopy (SEM). Results In group A, at the 6th week after operation, the interface region between implants and bone tissue became fuzziness, and was crossed by the generated fibers of bone tissue, and filled with woven bone growing inside into the composites; at the 12th week after operation, blood vessels, osteoblasts and new bone were generated inside of composites; at the 24th week after operation, the bone defects were recovered and became solid union, most of the implants were replaced by new bones. In group B, at the 6th week after operation, the interface of CPC and bone tissue was sharp, and was not crossed by new bones; at the 24th week after operation, the bone defects were still filled with materials of CPC and no new bone was found inside CPC. In group C, at the 24th week after operation, the interface of bone cement and bone remained non-union. Higher osteoblastic activity,more neogenetic blood vessels and higher growth rate of woven bone were observed in group A compared with those in group B. Conclusions For bone defect, the implantation of composites with DBM proportion of 0.2 can stimulate the growth of osteoblast, blood vessel and woven bone. It is biodegradable and can be replaced by autogenous bone.