上颌中切牙全瓷冠纤维桩与复合树脂核在两种边界条件下的应力分析

摘要背景：以往应用三维有限元对桩核修复体的研究中，对在不同边界条件下的应力分析报道较少。 目的：应用三维有限元法分析两种边界条件下，上颌中切牙全瓷冠纤维复合树脂桩核修复后的应力变化。 方法：使用三维螺旋CT，对受试者上颌中切牙进行连续扫描，并输入Mimics10.01软件中，建立两组相同的三维有限元模型。分别定义两组的边界条件为摩擦关系和全约束关系。在有限元分析软件Abaqus中，分析两种边界条件下全瓷冠、剩余牙本质和玻璃纤维桩的Von Mises应力及最大主应力。 结果与结论：全瓷冠、剩余牙本质在摩擦关系下的应力峰值明显增高；纤维桩在两种边界关系下的应力峰值相差甚小；两种边界关系下各部分组织的应力分布基本相同；提示边界条件不会改变原有组织的应力分布，但其对应力峰值影响较大，纤维桩不会降低剩余牙本质的应力峰值。

Stress analysis of maxillary central incisors restored with all-ceramic crown fiber post and composite resin core under two boundary conditions

AbstractBACKGROUND: Restoration with post and core has been studied extensively by three-dimensional finite element method, but stress analysis under different boundary conditions has not been reported.OBJECTIVE: After maxillary central incisors restored with all-ceramic crown fiber composite resin posts and cores, stress change under different boundary conditions is analyzed by three-dimensional finite element method.METHODS: Maxillary central incisors of the involved subjects were scanned consecutively by three-dimensional spir CT, dicom data was used for establishing two sets of the same three-dimensional finite element models with medical image manipulation soft, Mimics10.01. The boundary conditions of two sets of models were defined friction relationships and all constraint relationships. Von mises stress and max principal stress of all-ceramic crown, residuary dentin and fiber post under two boundary conditions were analyzed by finite element analysis soft, Abaqus6.7. RESULTS AND CONCLUSION: In friction relationships, the stress peak of all-ceramic crown and residuary dentin remarkably increased; while the peak of fiber post under two boundary conditions were almost similar; stress distributions of every unit were similar; it is indicated that boundary conditions cannot change the stress distribution of original tissues, but greatly influences the stress peak, fiber post will not reduce the peak stress of residual dentin.