一个治疗周期内尖牙倾斜移动过程模拟的应力分析  

Stress Analysis of the Dynamic Process Simulation of Canine Tipping Movement during a Therapy Period

作　　者：钱英莉[1] 樊瑜波[2] 刘展[1] 

机构地区：[1]四川大学生物力学工程实验室,四川成都610065 [2]北京航空航天大学生物工程系,北京100083

出　　处：《四川大学学报（工程科学版）》2007年第6期66-70,共5页Journal of Sichuan University (Engineering Science Edition)

基　　金：国家自然科学基金资助项目(10529202);四川大学青年科学研究基金资助(校青06014)

摘　　要：将骨重建过程与有限元分析相结合,对尖牙在一个治疗周期内的倾斜移动过程进行模拟并得到各阶段的应力分布。选用一个正畸患者的下颌尖牙,建立包括牙齿、牙周膜、牙髓、牙槽骨的三维实体模型,通过有限元计算得到初始应变分布。以牙周膜外表面的正应变作为牙槽骨吸收的力学刺激,计算出牙槽骨在每周的吸收量然后确定牙齿的倾斜角度;以牙齿移动后的位置重新建立模型,并施加衰减后的正畸力值再次计算牙周膜的应变分布,作为下一阶段的初始状态。结果表明,一个治疗周期内,尖牙的移动曲线基本符合典型牙移动的3个阶段;牙槽骨和牙周膜的应力逐渐下降,且最大应力都出现在牙根尖或牙槽骨嵴顶位置。实现了尖牙在正畸力作用下发生倾斜移动的动态过程的模拟,可为临床上制定方案和预测效果提供参考。With combining bone remodeling with finite element analysis, the dynamic process of canine tipping movement during a therapy period is simulated and the stress distribution in each phase is obtained. A three-dimensional finite element model including tooth, periodontal ligament, pulp and alveolar bone is established according to a mandibular canine of an orthodontic patient. Through finite element analysis, the strain distribution of the model is obtained under the initial moment. The normal strain on the surface of the periodontal ligament is assumed as the mechanical stimulus proportional to the absorption rate of alveolar bone in each week. Then the second model based on the moved canine is constructed. With the decreased moment, the computed normal strain of the periodontal ligament surface is also used for the next phase of tooth tipping movement. In a therapy period, the relationship between the time and the degree in the numerical simulation is consistent with typical tooth movement. The stresse in the alveolar bone and periodontal ligament gradually decreases and the maximum stress appears at the tooth apex or the crest of alveolar bone. The dynamic process simulation of canine tipping movement is achieved. It will be helpful for the planning and forecast of the therapy.

关 键 词：尖牙 倾斜移动 动态过程 有限元 

分 类 号：R318.01[医药卫生—生物医学工程]