上颌第一磨牙弯曲牙根生物组织应力的三维有限元分析

摘要

BACKGROUND:The stress distribution in the periodontal ligament of bending root can provide reference for the size and manner of force in orthodontic treatment. On this account, it can optimize the design of orthodontic force. OBJECTIVE:To analyze the stress distribution of root and periodontal ligament in the bending roots of the maxil ary first molar under different orthodontic forces. METHODS:The maxil ary first molars with normal roots and bending roots were selected, and then the finite element models of maxil ary first molars and periodontal ligaments were established through CT scan and Workbench 11.0 finite element analysis software. The models were loaded with six different methods to analyze the stress distribution. RESULTS AND CONCLUSION:The stress distribution of bending root was mainly concentrated in the tooth neck, fol owed by the apex. During the overal tooth movement, the stress was smal est on the root, periodontal ligament and alveolar bone. Correction of bending roots needs more accurate positioning and traction.%　　背景：根据弯根牙牙周膜应力分布为口腔临床工作者提供正畸施力的方式和大小，以此来优化正畸力系统设计。　　目的：探讨上颌第一磨牙弯曲牙根受到正畸力作用下牙根及牙周膜的应力分布情况。　　方法：选用正常形态和牙根弯曲的上颌第一磨牙作为建模素材，应用CT机扫描，ANSYS Workbench 11.0有限元分析软件建立上颌第一磨牙及其牙周膜的有限元模型，应用6种不同载荷方式对模型进行加载，分析其应力分布情况。　　结果与结论：弯根牙应力集中区主要在牙颈部，其次是根尖部，牙齿在做整体移动时其牙根、牙周膜、牙槽骨应力最小。对于弯根牙的矫治需要更准确的定位以及更合理的牵引力。