种植体支抗内收上颌全牙列的三维有限元分析

摘要

Objective; To investigate the biomechanical effects of micro-implant anchorage for en-masse retraction of the maxillary dentition with different retraction hook heights. Methods; The three-dimensional finite element model of the maxillary dentition en-masse retraction with micro-implant anchorage was constructed with CT scanning data, MIMICS, CADTIA and SOLIDWORKS software. Then the force and the initial tooth displacement was calculated when the retraction hook height was 1,4,7 and 10 mm under the load of 3N, respectively. Results; With retraction hook height increasing the sagittal force increased, while the vertical force decreased, the whole upper dentition rotation changed from clockwise to counter-clockwise. Conclusions 1. The upper dentition movement can be changed effectively by the retraction hook with different heights. 2. The center of resistance of maxillary dentition is located 9 to 12 mm above the occlusal plane.%目的:研究在种植体支抗内收全牙列的过程中,不同的牵引钩高度对上颌全牙列的生物力学效应和影响.方法:运用螺旋CT,MIMICS、CADTIA和SOLIDWORKS软件,建立微种植体支抗内收全牙列的三维有限元模型,并计算在3N正畸力负载下上颌全牙列在牵引钩高度为1、4、7、10 mm时的受力大小和初始位移.结果:随着牵引钩高度的增加,矢状向力逐渐增加而垂直向力逐渐减小,上牙列逐渐由顺时针变为逆时针方向旋转.结论:通过改变牵引钩的高度,可以有效地改变上牙列的移动方式；上牙列的阻抗中心的高度位于(牙合)平面上方9～12 mm之间.