釉质发育不全磨牙的微观磨损性能研究

Nano-scratch research of amelogenesis imperfecta teeth

目的对比研究釉质发育不全磨牙的微观摩擦磨损性能。方法分别采用原子力显微镜(AFM)、能量色散X线光谱仪(EDX)对釉质发育不全牙及正常牙进行微观形貌观察和物质成分分析;通过纳米划痕技术并结合扫描电镜(SEM)对比分析其微观摩擦磨损性能上的差异。结果 AFM图显示釉质发育不全牙釉质比正常牙釉质连接疏松且可见有孔状结构,粗糙度大。EDX检测发现釉质发育不全牙釉质Ca、P含量较正常牙低,C含量较正常牙高。釉质发育不全牙釉质在同等载荷下较正常牙的摩擦系数大,破坏严重。结论釉质发育不全牙与正常牙在微观结构、物质组成和微观摩擦磨损上均有较大差异。在临床上对釉质发育不全牙做修复时,应充分考虑这一因素。

Objective To study the differences between amelogenesis impeffeeta （AI） teeth and normal human （NH） teeth in wear properties. Methods The uhrastructure of the human tooth enamel from adult patient diagnosed with AI was investigated using atomic force microscope （AFM） and compared with the surface of normal human tooth enamel. The composition of tooth enamel of AI teeth and normal human teeth were analyzed by energydispersive X-ray spec- troscopy（EDX）. The properties of micro-friction and wear between AI teeth and normal human teeth were compared using nano-scratch technology and scanning electron microscope （SEM）. Results The AI teeth were found porosity and the loosely packed hydroxyapatite was distributed randomly compared with normal human teeth. The amount of C was higher while the amount of Ca, P were lower in AI teeth than normal human teeth. The flietion coefficient of both AI teeth and normal human teeth was increasing with the load increased and the friction coefficient of AI teeth was higher than normal human teeth with the same load. Meanwhile, the destruction of AI teeth was more severe than normal human teeth with the same load. Conclusion The AI teeth has significant differences with normal human teeth on micro-structure, composition and micro-friction and wear properties. Thus, we need to have a general consideration of all these results when doing clinical restorations.