上颌中切牙多孔金属牙桩的设计及有限元分析

Design and Finite Element Analysis of Upper Incisor with Porous Metal Post-Cores

为了设计一种表面带有多孔结构的金属牙桩,比较多孔金属牙桩和铸造桩修复上颌中切牙后的应力分布,采用上颌中切牙建立多孔金属牙桩修复后的三维有限元模型,牙桩的表面设计成孔隙率分别为15.5%,26.2%,40.2%,59.2%的多孔结构,并进行有限元分析。分析表明随着牙桩表面多孔结构的孔隙率增加,牙根上的最大主应力增加,牙桩内部实心结构和外部多孔结构的等效应力增加,多孔结构的等效应力大于实心结构的等效应力。研究得出结论:孔隙率可以调整降低金属牙桩表面的弹性模量和抗压强度,有利于保护牙根。

To design a kind of post-core with porous structures above its surface, the stress distribution of upper incisor restored with porous metal post-cores was compared in different structures. The 3D finite element models of the upper incisor with reparingporous metal post-cores was constructed. The surface of metal post-cores was designed in four porosities of 15.5%, 26.2%, 40.2%, 59.2% ,and the finite element analysis was carried out. The results show that with the increase of porosity of post-cores＇ surface, the maximum stress of dentin increases, and the maximum stress of solid part and porous part increase, but the maximum raise stress of porous structures was higher than solid structures. It is concluded that porosity decreases elastic modulus and compressive strength of metal post-cores, which can protect root in a better way.