全下颌改良杆卡式种植覆盖义齿受冲击载荷的三维各向异性有限元分析

A Three Dimensional Anisotropic Finite Element Analysis of Modified Bar Clip Implant Borne Overdenture in the Edentulous Mandible Under Punching Loads

用三维各向异性有限元法分析全下颌改良杆卡式种植覆盖义齿受冲击载荷下的应力分布，分别使用烤瓷和塑料两种人工牙材料，目的是了解应力分布规律，考察在冲击载荷下不同人工牙材料对应力的影响。结果发现，烤瓷人工牙作为上部结构时种植体的应力峰值高于塑料人工牙，但是种植体骨界面的应力峰值较为接近，使用塑料牙时，种植体骨界面的应力分布较均匀。提示在冲击载荷下，烤瓷和塑料人工牙材料对应力分布有一定的影响；塑料牙对冲击载荷有一定的缓冲作用，可以降低种植体的应力峰值；冲击载荷对种植体骨界面的应力峰值影响不大，故烤瓷和塑料均可以作为全下颌改良杆卡式种植覆盖义齿的人工牙材料。

The stress distributions of the modified bar clip implant borne overdenture in the edentulous mandible were performed under punching loads with both porcelain and resin chosen as the restorative materials by means of three dimensional anisotropic finite element method. The purpose of this study was to investigate the patterns of stress distributions and to compare the effect of different restorative materials on the stress distributions under punching loads. The results showed that the value of stress peaks in implants with porcelain restorations seemed higher than those with resin restorations. On the contrary, in the bone implant interface had little difference, except a comparative uniform stress distribution found in resin restorations, It implies that resin restoration produces a cushioning effect on reducing the stress peaks in implants themselves under punching loads. Both porcelain and resin restorations can be chosen as the restorative materials because of a little influence on the stress peaks in bone implant interface under punching loads.