颗粒骨的制备及修复骨缺损的研究

The preparation and the ability of the morsefized bone in repairing bone defects

目的观察聚磷酸钙纤维（CPPF）磷酸钙骨水泥（CPC）、微小颗粒骨复合物体外降解特性及体内修复骨缺损的能力。方法将CPPF、CPC、微小颗粒骨按质量比1：4：4制成复合人工骨，通过PH值、重量、抗压强度的变化，观察人工骨在pH7．4的37℃磷酸盐缓冲液（PBS）中的降解性能。通过大体、X光片、组织学观察及力学测试来检测复合人工骨的体内修复骨缺损的能力。结果体外实验证实：CPPF／CPC／颗粒骨复合材料孔隙率为72．1％，CPC／颗粒骨孔隙率为58．2％；扫描电镜显示CPPF／CPC／颗粒骨复合材料的孔径为100～400μm，CPC／颗粒骨为50～300μm；两组样品溶液pH值在12周内基本维持恒定；CPPF／CPC／颗粒骨复合材料0～4周重量变化较小，4～8周下降较快，12周为初始重量50％，CPC／颗粒骨复合材料在0～6周变化较小，6周后重量下降较快，12周时为初始重量70％；CPPF／CPC／颗粒骨复合材料初始抗压强度9．28MPa，CPC／颗粒骨复合材料初始抗压强度6．21Mpa，两者有统计学意义。CPPF／CPC／颗粒骨强度在0～4周下降较慢，4周后下降较快，12周时为0．18MPa，CPC／颗粒骨强度均匀下降，12周时为0．24MPa。体内实验：CPPF／CPC／颗粒骨复合材料修复骨缺损效果优于其他各组，且差异有统计学意义（P〈0．05）。结论复合材料以其优良的生物学性能有望成为理想的骨替代材料。

Objective To explore the degradation characteristics of the composite of calcium polyphosphate fiber （CPPF） ,calcium phosphate cement （CPC） ,micromorselized bone in vitro and the ability in repairing bone defects in vivo. Methods A blend method was developed to prepare the composite of CPPF/CPC/micromorselized bone on the weight rate of CPPF： CPC ：micromorselized bone = 1：4： 4. The gap diameter was observed by scanning electron microscope. In vitro, the composite was put into PBS （pH 7.4） ; the PH value,weight and biomechanics of them were determined during the degradation. In vivo, the effect was observed by grass, X-ray, histopathological, scanning electron microscopic and dynamic examinations 2, 4,8,12 weeks after operation. Results In vitro,scaning electron microscopy revealed that the pore diameter of CPPF/CPC/micromorselized bone composite was 100-400 μm, the porosity was 72.1%, while the CPC/ micromorselized bone composite was 50-300 μm, the porosity was 58.2%. During degradation, the pH values of beth the two composite were kept steady at the end of 12th week. The weight of CPPF/CPC/micromorselized bone was slightly decreased within 4 weeks, then decreased obviously and remained 50% of its prime weight at the end of the 12th week; while the weight of CPC/micromorselized bone was slightly decreased within 6 weeks ,then decreased obviously and remained 70% of its prime weight at the end of the 12th week. The prime biomechanical strength was 9.28 Mpa in CPPF/CPC/micromorselized bone and 6.21 Mpa in CPC/micromorselized bone respectively. There was significant difference between them （ P 〈 0. 05 ）. The strength of CPPF/CPC/micromorselized bone was decreased slowly within 4 weeks, then decreased obviously and was 0. 18 Mpa at the end of 12th week; the strength of CPC/micromorselized bone was decreased symmetrically and was 0.24 Mpa at the end of 12 week. In vivo,the ability of CPPF/CPC/micromorselized bone in repairing bone defect was better than the other groups. There was significant difference between them （P 〈 0.05）. Conclusion The composite of CPPF/CPC/micromorselized bone may be one of ideal scaffolds engineering for its good biocharacteristics in repairing bone defect in bone engineering.