【摘要】 目的通过体内、外降解实验来探索超高压技术合成的HA/PLGA生物骨折内固定材料的降解规律。方法将HA/PLGA样品置于恒温SBF液中,定期测试失重率、平均分子量,并对试件作扫描电镜观察;同时将HA/PLGA样品置于新西兰白兔皮下、骨内,定期做光镜和电镜观察。结果HA/PLGA材料在体外的水解过程中,随着材料表面HA颗粒的脱落,水分子渐入材料内部,表现为早期平均分子量的降低,晚期失重率的升高。体内实验观测到材料逐渐被机体组织利用,并有血管等组织进入材料深部,形成对材料的持续性降解。结论高压合成的HA/PLGA在体内实验期间显示出良好的组织相容性,并具有生物降解特性,可被机体利用形成新生骨组织。更多还原

【Abstract】 Objective To investigate the biodegradation mechanism of the HA/PLGA composite rods for internal fixation of bone fractures. Methods The HA/PLGA samples were immersed in the simulated body fluid (SBF) at 37℃. The average molecular weight and the ratio of the losing weight were measured periodically in vitro. In vivo study the samples of HA/PLGA were implanted subcutaneously and in the medullary cavities of News Zealand rabbits . The specimens were examined histologically by light microscope. The rod surfaces were examined using a scanning electron microscope. Results In the initial hydrolysis process of HA/PLGA, HA particles detached from the rod surface and water infiltrated into the rod. The average molecular weight dropped while the weight loss ration increased . In vivo observation showed that the biodegradable material was used by the body. New vessels grew into the samples to facilitate further degradation. Conclusion The HA/PLGA composite is biocompatible. It is also biodegradable and allows new bone formation.更多还原