桩核材料和咬合状态对牙本质应力分布影响的分析

目的：应用三维有限元法研究不同咬合状态对不同桩核系统修复后的上颌中切牙牙本质应力分布的影响。方法：采用螺旋CT扫描建立上颌中切牙的有限元模型。在此基础上,模拟四种咬合状态,分析镍铬合金,玻璃纤维,铸造金合金以及二氧化锆修复后牙本质的应力分布。结果：咬合状态对应力分布有一定的影响。采用纤维桩修复时,根尖1/3牙本质的应力值最小。结论：在前牙的桩核冠设计制作时,不仅要注重桩核材料的选择,也要注重考虑患者的咬合状态,优化设计使应力分布更合理。

Three-dimensional finite element analysis of the material and occlusal contact on dentinal stress distribution

Objective： To investigate the relationship between various occlusal contacts, different post-core systems and the stress distribution of residual tooth structure. Methods： By SCT scanning, a three dimensional finite element model of maxillary central incisor restored was set p and analyzed after post-core restorations with four different materials, including cast Ni-Cr alloy, fiber post, cast gold alloy and ZrO2. Results： The stress distribution varied together with different occlusal contacts. The stress level at the apical third of the tooth restored with the fiber post is the smallest. Conclusion： Not only the post-core system but also the occlusal contact should be considerd sufficiently to improve the design of post and tooth preparation.