减阻牵张成骨远移尖牙的三维有限元分析

背景：牙周膜牵张成骨通过力作用于牙周膜，带动牙齿移动；牙槽骨牵张成骨是通过整个骨盘的位移，达到牙齿移动的效果。目的：建立基于健康成人的、3种不同状态下的上下颌三维有限元模型，采用三维有限元方法对比研究3种模型在力的加载下应力分布和瞬时位移情况。方法：模型1通过多种软件结合建立常规状态下、模型2建立牙周膜减阻牵张成骨后、模型3建立牙槽骨减阻牵张成骨后移动尖牙的三维有限元模型，分别模拟力的加载。结果与结论：3种模型的最大瞬时位移均发生在尖牙近中牙冠上1/3处，其值模型＜模型3＜模型1；最大等效应力均位于上颌尖牙远中侧牙槽嵴处，其值模型2＜模型1＜模型3。说明牙槽骨和牙周膜减阻牵张成骨均能有效减小牙移动阻力，增加尖牙瞬时位移，且去除尖牙远中骨质效果更为显著。两种方法成功避免了支抗丧失，但尖牙存在远中倾斜趋势，临床工作中应采取相应措施加以控制。

Three-dimensional finite element analysis of canine distalizaUon through reducing resistance and distraction osteogenesis

BACKGROUND：Peridental membrane distraction osteogenesis exerts the functions at peridental membrane and leads to tooth movement. Alveolar bone distraction osteogenesis produces tooth movement through the displacement of the whole bone plate.OBJECTIVE：To establish three-dimensional finite element model of upper and lower jaw of healthy adults under three different conditions, and to compare the stress distribution and distal movement of the models using three-dimensional finite element analysis method.METHODS：Model 1：three-dimensional finite element model of the canine under normal conditions using avariety of software;Model 2：three-dimensional finite element model of the canine after distracting osteggenesis of the periodontal ligament;Model 3, three-dimensional finite element model of the canine after reducing resistance and distracting osteggenesis of the alveolar bone. The force loadings were stimulated among these models.RESULTS AND CONCLUSION：The biggest displacements on those three models occurred in canine crown on 1/3, and the displacement quantity on canine was model 2〈model 3〈model 1. The biggest equivalent stress concentrated in distal alveolar crest, and the equivalent stress was model 2＆lt;model 1＆lt;model 3. In the process of canine distal movement, reducing bone resistance and distracting osteggenesis, especial y distal alveolar crest of canine, can accelerate the tooth moving speed effectively. And the two ways successful y avoid the loss of anchorage. We should notice that the canine has distal motion tendency under the action of force, appropriate measures should be taken to control it in clinical work.