金合金桩核冠修复下颌第一磨牙两壁缺损的三维有限元分析

背景：牙本质缺损的位置可能会影响牙根应力分布。 目的：对金合金桩核全瓷冠修复的根管治疗后两壁缺损下颌第一磨牙进行三维有限元应力分析，为临床治疗方案的选择提供理论指导。 方法：通过牙科CT扫描，提取数据，MINCIS软件进行三维重建，GEOMAGIC转换曲面，ANSYS布尔运算建立下颌第一磨牙两壁缺损金合金桩核全瓷冠修复6种模型。在4种载荷下，分别比较牙本质Mohr应力分布及牙本质最大Mohr值。 结果与结论：下颌第一磨牙6种缺损模型在金合金桩核全瓷冠修复时，牙根应力分布及最大应力差异无显著性意义。结果证实，金合金桩核全瓷冠修复时，下颌第一磨牙牙冠两壁缺损时，牙壁缺损的位置对修复效果无明显影响。

Three-dimensional finite element analysis of gold alloy post-core in the repair of structure defects of the mandibular first molar

BACKGROUND：The location of residual dentin may affect stress distribution of tooth root. OBJECTIVE：To make a three-dimensional finite element analysis of gold al oy post-core and al-ceramic crown in the repair of structure defects of the mandibular first molar, and to provide a guideline for planning restoration for such kind of tooth structure defects. METHODS：Three-dimensional finite element models of the restored first mandibular molars were constructed by CT image reconstruction technique. Then MIMICS software was used to separate the areas and finish the three-dimensional calculation. GEOMAGIC software was also applied to modify and generate a NURBS surface in each patch. Al components of the models were assembled under the ANSYS preprocessor. The Mohr strength theory was applied for comparing the maximum Mohr stress value of dentin and stress concentration areas in six models under different simulating loads. RESULTS AND CONCLUSION：The restoration effects in six models were compared, the maximum Mohr stress value of dentin and stress concentration areas were not obviously different. The location of residual dentin has little influence on the stress value and distribution, when restored by gold al oy post-core and and al-ceramic crown.