摘要
报道了多孔生物 β Ca3(PO4 ) 2 降解材料的研制工艺 ,同时结合动物实验及扫描电镜等测试手段对这种材料的结构特点及有关性能进行了讨论 .所研制的材料中含有大量的气孔 ,其孔经大概为 30 0～ 5 0 0μm .动物实验结构表明这种材料植入体内将具有良好的生物相容及降解性能 .当材料植入动物内二个月内 ,与宿主骨之间的间隙完全愈合 ,但外形及密度变化不大 .植入 6个月后 ,两端的新骨向中心区生长 ,材料开始降解 ,边缘出现不整齐状 .文章的最后部分讨论了所制材料在动物体内的降解过程 .关于 β Ca3(PO4 ) 2 陶瓷的生物降解机理 ,目前还没有统一认识 ,可以认为 :材料在动物体内降解是由于细小晶粒被生物细胞吞噬的结果 .同时 ,化学沉积是材料降解的另一个重要原因 .材料的降解是从玻璃连结相开始突破的 ,其过程可以描述为 :当材料植入动物体内后 ,骨组织沿材料孔隙长入 ,同时连结晶粒的玻璃相在体液作用下发生水解 ,并伴随晶相颗粒的分离 .分离过程中小晶粒被生物细胞吞噬 ,残留大晶粒在组织液中存在下列溶解平衡Ca3(PO4 ) 2 3Ca2 ++ 2PO2 - 4溶解出的一部分Ca2 +随体内代谢被排出体外 ,另一部分在体液与血清作用下沉积在新生骨上 .由于大晶粒难以被细胞吞噬 ,溶解度相对又较小 。
This paper reports a technique of preparing porous biodegradable β?Ca 3(PO 4) 2 ceramic material. The properties and structural characters of this material are discussed along with other measurements and animal tests. The material contains a large number of pores whose sizes are about 300～500 μm. The results show that this material possesses superior biocompatibility and degradation after it is implanted in the body. When the material is implanted in an animal for 2 months, the gap between the material and the bone is completely healed, but the appearance and density of the material have not changed. After 6 months, the new bone grows towards the implanted material, and at the same time the material begins to degrade and the fringe becomes irregular. The biodegradable mechanism of the specimens is also analyzed in this paper. It is thought that the degradation of implanted material is the result of fine crystal grain being engulfed by cells. At the same time, the chemical deposition is another important reason for the degradation.
出处
《南京大学学报（自然科学版）》
CAS
CSCD
北大核心
2002年第4期494-498,共5页
Journal of Nanjing University（Natural Science）
