正畸力作用下上颌尖牙牙周膜的应力应变分布

摘要

背景 口腔临床工作者可以根据牙周膜应力分布控制正畸施力的方式和大小,从而优化正畸力系统设计.目的 分析正畸力载荷作用下牙周膜的应力应变分布.方法 将上颌尖牙牙根近似为抛物线形柱体模型,分析上颌尖牙牙根在正畸力作用下牙周膜应力应变分布.对模型加载、求解,对近似模型在剪力、轴力、弯矩以及扭矩分别作用下牙周膜应力应变分布进行分析,并将计算结果应用到正畸力作用下牙周膜应力应变分析.结果与结论 实验结果显示有限元分析和理论计算结果差别较小,最大为13.4%,并且高应力区出现在牙槽嵴顶部截面.正畸力作用下牙周膜中应力应变分布比较复杂,应力应变分布不仅与牙根长度,还与不同的加载力系统有关.因此临床治疗过程中,口腔医生应适当地考虑这些因素.%BACKGROUND: The stress-strain analysis of the periodontal ligament under the orthodontic force can provide theoretical basis for the orthodontics design.OBJECTIVE: To analyze the stress and strain distributions of periodontal ligament of maxillary canine under the orthodontics force.METHODS: The stress and strain distributions of periodontal ligament of maxillary canine were analyzed under the orthodontics force by assuming the root of maxillary canine to be paraboloidal shape model. The model was loaded and solved; the approximate shear force, axial force, bending moment and torque were loaded on the model in order to analyze the stress and strain distributions of the periodontal ligament.RESULTS AND CONCLUSION: The results of theoretical analysis and numerical results of stress distribution in the periodontal ligament were very similar, the maximum difference value was 13.4%, and the largest Von misses stress of the periodontal ligament was in the alveolar crest. The results show that the stress and strain distributions of the periodontal ligament were complicated; they were not only related with the root length, but also related with different load power system. The dentist should rationally take all these parameters into account in the clinical treatment.