镁锌合金骨螺钉表面防降解改性涂层的制备与性能

Preparation and Properties of Modified Anti-degradation Coating on the Surface of Mg-Zn Alloy Bone Screws

采用电化学沉积方法在镁锌合金骨螺钉表面制备了无氟和含氟(FHA)的钙磷盐防降解涂层,并在模拟人体体液中进行体外降解试验,采用扫描电镜和X射线衍射仪等分析了降解前后涂层的形貌与晶体结构。结果表明:无氟涂层为丝状和块状结构,而含氟涂层为柱状结构;无氟和FHA钙磷盐涂层都可以有效减缓镁合金在模拟人体体液中的腐蚀,前者比后者的效果更佳;FHA涂层不易溶解,但与外形复杂的螺钉结合不牢,且其质脆,浸泡过程中易于脱落;无氟涂层则能保持完整性,可以对骨螺钉起到更好的保护作用。

The anti-degradation coatings of Ca-P with or without F on the surface of Mg-Zn alloy bone screws were prepared by the method of electro-deposition. In vitro degradation of these screws in simulated body fluid （SBF） was investigated. The morphology and the crystal structure before and after degradation of the two kinds of Ca-P coatings were researched by scanning electronic microscope （SEM） and X-ray diffraction （XRD）. The results showed that the surface of the Ca-P coating without F contained lumpish and filamentous structure, while that of the coating with F was columnar. The coatings with or without F can both retard the corrosion of the screw effectively. The screws coated with FHA degraded faster than the screws coated with the coating without F. The FHA coating was resistant to the corrosion. However it couldn＇t combine quite well with the complex-shaped screw, coupled with its brittleness, and it tended to peel off. In contrast, the screws with the coating without F maintained integrity, which protect the bone screws effectively.