Experimental Study Of Repairing Rabbit Bone Defects With Calcium Alginate Film And Complex Of NGF-BMG

Objective: In this study, we employed a recent membrane guided bone regeneration technique to enhance healing of long bone defect. We combined guided bone regeneration with osteoinductive and osteocondutive effects by using calcium alginate film (CAF) and bone matrix gelatin (BMG) associated with nerve growth factor (NGF).The purpose of this study is to observe how NGF repair bone defects and learn feasibility of NGF delayed release body, another purpose of this study is to explore effect of NGF combined guided bone regeneration in healing of long bone defect. In order to find an effective method to repair bone defects in clinic.Methods: 1. Experimental study of complex of NGF-BMG liberating NGF in rabbit vivo. Complex of NGF-BMG was made from putting solution of nerve growth factor into BMG by vacuum adsorption and freeze-drying techniques. The sustaining period of NGF concentration in rabbit vivo after implantation of NGF-BMG was examined by enzyme-linked immunosorbent assay (ELISA).2. Experimental study of repairing rabbit bone defects with calcium alginate film and complex of NGF-BMG. 24 adult male New Zealand rabbits were divided into 4 groups of 6 animals each at random. They were operated into standard bone defect experimental models in the amphi-radius by resected 10mm radius bone. Group A were bone defect with transplantation of CAF/ complex of NGF-BMG; Group B were transplantation of CAF/BMG; Group C were transplantation of CAF/NGF; Group D were the same bone defect with only transplantation of CAF. Gross observation, histological analysis and X-ray films were taken at 4, 8, 12 week postoperatively, biomechanical test was performed at 12 week postoperatively. The evaluated results of histological analysis, X-ray films and biomechanical test were tested by software SPSS13.0 of statistics. Result: 1.The NGF concentration of complex of NGF-BMG in local tissues were higher than that of plasma, and the NGF concentration in local tissues was higher in early stage, later it kept stable low drug release. 2. The results of group A are better than group B, C and D in histological analysis, X-ray films and biomechanical test (P<0.05).Conclusion: 1.Complex of NGF-BMG can gradually release NGF with effective drug concentration and has excellent ability to repair segmental long bone defects; 2.