上颌种植钉配合摇椅曲内收前牙的三维有限元应力分析

目的:通过改变摇椅曲度和游离牵引钩高度来分析牙齿的受力情况.方法:采用螺旋CT扫描,Mimics建模软件和Ansys分析软件,建立上牙列及其支持组织、以及不同曲度摇椅曲(5°、10°、15°、20°、25°)和不同高度的牵引钩(2.1mm、4.0 mm、5.5 mm)模型,施加1.5N向后的内收力.结果:牙齿受到的应力值大于牙周膜,牙齿应力集中区主要在托槽和颊面管区域,牙周膜主要在牙颈部.尖牙受到的应力值最大,其次是侧切牙.结论:牙齿和牙周膜所受到的最大应力都是随着摇椅曲和游离牵引钩高度的增加而增大.

Three Dimensional Finite Element Analysis of Tooth Stress Distribution in Maxillary Using Mini-screw Cooperated with Upper Accentuated-curve to Close Tooth Space

Objective: To analyse the stress distribution of tooth through changing the angle of the upper accentuated-curve archwires and the height of the free traction hook.Methods: Spiral CT scanning,Mimics and Ansys software were employed in this study to construct the three-dimensional finite element model of maxillary teeth,periodontal ligaments and alveolar bone as well as the 0.019×0.025 inch upper accentuated-curve stainless steel archwires with different angles(5°,10°,15°,20°,25°) and the free traction hook with different height(2.1 mm,4.0 mm,5.5 mm)and exerting 1.5 N backward force.Results: The results show that teeth stress value is larger than periodontal.Teeth stress mainly distributed in braces and around baccal tube,while periodontal stress mainly distributed in the neck of tooth.Stress value of the canine was the largest,second was the lateral incisor.Conclusion: With the angle of upper accentuated-curve archwires and the height of free traction hook increased,each teeth and periodontal stress value increased.