Abstract：
OBJECTIVE: Altering the position and orientation of the root canal access cavity passway, or modifying the reduction of dentin volume, can influence the strength of dentition. This study aimed to compare the effects of different access cavities on the biomechanical performances of maxillary central incisors with a finite element analysis.
METHODS: Based on the micro-computed tomography (CT) scan of a maxillary central incisor, the finite element models of the intact tooth and teeth with 4 access cavity designs: conservative incisal access cavity, incisal access cavity, conservative access cavity, and traditional access cavity were generated. Simulated occlusal forces were applied at the incisal edge of the incisor in the finite element analysis procedure.
RESULTS: The maximum von Mises stress and maximum principal stress in the cervical area are highest in the traditional access cavity group, followed by the conservative access cavity group, incisal access cavity group, and conservative incisal access cavity group.
CONCLUSIONS: The conservative access cavities minimise the extent of dentin removal from the cervical region, protecting the mechanical behaviour of the incisor. Moving the access cavity entry point to the incisal edge also improves the fracture resistance of the incisor.
CONCLUSIONS: This study\'s findings would help clinicians select the most appropriate endodontics access cavity method when performing the root canal on maxillary central incisors.
METHODS: Based on the micro-computed tomography (CT) scan of a maxillary central incisor, the finite element models of the intact tooth and teeth with 4 access cavity designs: conservative incisal access cavity, incisal access cavity, conservative access cavity, and traditional access cavity were generated. Simulated occlusal forces were applied at the incisal edge of the incisor in the finite element analysis procedure.
RESULTS: The maximum von Mises stress and maximum principal stress in the cervical area are highest in the traditional access cavity group, followed by the conservative access cavity group, incisal access cavity group, and conservative incisal access cavity group.
CONCLUSIONS: The conservative access cavities minimise the extent of dentin removal from the cervical region, protecting the mechanical behaviour of the incisor. Moving the access cavity entry point to the incisal edge also improves the fracture resistance of the incisor.
CONCLUSIONS: This study\'s findings would help clinicians select the most appropriate endodontics access cavity method when performing the root canal on maxillary central incisors.
摘要：
目的：改变根管进入腔通道的位置和方向，或者改变牙本质体积的减少，会影响牙列的强度。本研究旨在通过有限元分析比较不同入路腔对上颌中切牙生物力学性能的影响。
方法：基于上颌中切牙的显微计算机断层扫描（CT）扫描，完整牙齿的有限元模型和具有4个进入腔设计的牙齿：保守的切面进入腔，切头进入腔,保守的进入腔，并产生了传统的进入腔。在有限元分析程序中，在门牙的切缘处施加了模拟的咬合力。
结果：宫颈区域的最大vonMises应力和最大主应力在传统通道腔组中最高，其次是保守的进入腔组，切入腔组,和保守的切门腔组。
结论：保守的进入腔可以最大程度地减少从宫颈区域去除牙本质的程度，保护切牙的机械性能。将进入腔进入点移动到切牙边缘还提高了门牙的抗断裂性。
结论：这项研究的发现将有助于临床医生在上颌中切牙进行根管时选择最合适的牙髓入腔方法。
方法：基于上颌中切牙的显微计算机断层扫描（CT）扫描，完整牙齿的有限元模型和具有4个进入腔设计的牙齿：保守的切面进入腔，切头进入腔,保守的进入腔，并产生了传统的进入腔。在有限元分析程序中，在门牙的切缘处施加了模拟的咬合力。
结果：宫颈区域的最大vonMises应力和最大主应力在传统通道腔组中最高，其次是保守的进入腔组，切入腔组,和保守的切门腔组。
结论：保守的进入腔可以最大程度地减少从宫颈区域去除牙本质的程度，保护切牙的机械性能。将进入腔进入点移动到切牙边缘还提高了门牙的抗断裂性。
结论：这项研究的发现将有助于临床医生在上颌中切牙进行根管时选择最合适的牙髓入腔方法。
