不同受力方式下上颌第一磨牙牙槽骨应力分布的有限元分析

Stress analysis of maxillary first molar alveolar bone under different orthodontics forces by means of finite element method

目的利用有限元的方法研究上颌第一磨牙在牙齿矫治过程中不同受力方式牙槽骨应力分布的特点。方法应用三维激光扫描的方法建立上颌第一磨牙、牙周膜、牙槽骨及颊面管的有限元模型,进行不同方式的加载并观察牙槽骨及其各个截面的应力分布。结果牙齿在单一水平力和垂直力作用下,上颌第一磨牙牙槽骨在牙颈部和根部分叉处出现应力集中;牙齿趋于整体移动时,上颌第一磨牙牙槽骨处于均匀的低应力分布,各应力都小于倾斜移动或旋转移动时的应力,牙槽骨的应力在根分叉平面稍大。结论不同受力方式下,上颌第一磨牙牙槽骨在牙颈部平面或根分叉平面应力最大,临床上应注意观察这些部位的变化;整体移动更有利于牙齿及牙周组织的健康。

Objective To observe the stress distribution of maxillary first molar alveolar bone under different orthodontic forces using finite element model.Method The finite element model was built by using advanced 3-dimensional laser scanning,comprising a maxillary first molar,periodontal ligament,alveolar bone,and a buccal tube.Different loads were applied at a point of the buccal tube and its stress of alveolar bone was analyzed.Result With a simple horizontal or vertical force,the stress pattern in the alveolar bone showed high concentration at the cervical level or furcation level. When the maxillary first molar was moving bodily, the stress of alveolar bone was uniform and comparatively small. Conclusions When the tooth obtained bodily movement, the stress of alveolar bone was uniform and low, which displays that the bodily movement profits the healthyof the alveolar bone. Since the biggest stress of the maxillary first molar alveolar bone was in cervial region or furcation level, the changes of these regions should be observed carefully