可切削生物活性微晶玻璃在模拟细胞外液中的界面行为

实验通过模拟细胞外液(PECF)浸泡、扫描电镜/能谱微区分析、薄膜XRD、红外反射光谱分析及原子吸收光谱分析等方法,研究了以氟金云母和氮磷灰石为主晶相的微晶玻璃在生理环境中表面生物活性反应过程和机理,认为微晶玻璃中残余玻璃相的Ca~(2+)、PO_4~(-3)溶出及溶液中Ca~(2+)、PO_4~(3-)及OH~-相对于羟基磷灰石的过饱和状态对于材料表面磷灰石层的形成具有重要意义。表面磷灰石层是由最初的无定形含水CaO—P_2O_5薄层晶化转变而成。

Surface Behavior of Machinable Bioaetive Glass Ceramic in PECF

The mechanism of bioactivity of the glass ceramic containing fluorapatitie and fluo- rophlogopite microcrystals was investigated by using the methods of in vitro and in vivo. The forma- tion process of hydroxylapatite laver on the glass ceramic surfaces in phsiological environment was re- searched with the techniques of SEM/EDAX, thin -film XRD, IRRS and atomicabsorption spectral analysis, and the formation mechanism of the hydroxylapatite layer waa discussed according to the characteristics of the composition and microstructure of the glass ceramic and the variety of the ions in Pseudo-Extracellular--Fluid(PECF). It was indicated that it was of primary importance to the forma- tion of the apatite layer that Ca~(2+)ions were leached from the residual glassy phase of the glass ceramic into PECF and, consequently, the fluid reached rapidly the supersaaturation with respect to hydroxy- lapatite. The apatite layer formed on the material surface had a lower degree of crystallization, and it was formed by crystallization of the previous amorphous film layer rich in CaO, P_2O_5 and H_2O.