| 摘要: |
| 目的：建立简化的微型种植体-骨三维有限元模型,研究不同植入方向下微型种植体-骨界面的生物力学变化,为微型种植体的临床应用提供理论依据。方法：应用I-DEAS有限元分析软件,将微型种植体以30°角倾斜植入骨块,在保持加载力方向、微型种植体与植入处骨表面夹角不变的情况下,以植入点为圆心,微型种植体在骨平面上的投影线为半径水平旋转180°,设定0°、45°、90°、135°、180°共5个植入方向。在与植入处骨表面平行的200 g力作用下,分析微型种植体-骨界面的应力分布及位移变化。结果：各组应力值及位移值的变化均符合临床生理要求,微型种植体的植入区、骨皮质区应力相对集中,Von-mises应力、拉应力、压应力分布变化总体一致,应力曲线整体呈递减趋势。在脱位力作用下,0°、45°组应力值小于其他组,0°组应力值最小,0°、45°组位移值明显高于90°、135°、180°组,90°组的位移值最小。结论：不同植入方向的微型种植体可以安全承载与植入处骨表面平行的200 g正畸力。临床上选择微型种植体植入方向时,尽量减小加载力对其的脱位作用,才更有利于微型种植体的稳定。 |
| 关键词: 牙种植体 有限元分析 生物力学 植入方向 |
| DOI：10.3724/SP.J.1008.2008.00829 |
| 投稿时间：2008-02-26修订日期：2008-03-24 |
| 基金项目: |
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| Three-dimensional finite element analysis of anchorage micro-implant with different embedding directions |
| WANG Han-si1,LI Xiao-zhi1*,LI Kang-ning2,ZENG Ming-hui1,HE Yan1 |
| (WANG Han-si1,LI Xiao-zhi1*,LI Kang-ning2,ZENG Ming-hui1,HE Yan1 ;2.Department of Fluid Mechanics,PLA Logistical Engineering University,Chongqing 400016) |
| Abstract: |
| Objective：To establish a simplified three-dimensional finite element model of orthodontic anchorage micro-implant,and to study the biomechanical changes of the micro-implant-bone interface when embedded in different directions,so as to provide a theoretical basis for clinical application of the micro-implant.Methods:I-DEAS finite element analysis software was used to establish a micro-implant and bone finite element model.The micro-implant was embedded into the bone at an angle of 30°.The orientation of the loading force and the embedding angle were kept unchanged; using the embedded point as the center of a circle and the projective line of micro-implant on the bone surface as the radius,5 different embedding directions,including 0°,45°,90°,135° and180°,were chosen.A simulated orthodontic force of 200 g was loaded parallel to the surface of bone in the embedded region,and the stress distribution and displacement changes on the micro-implant-bone interface were analyzed.Results:The changes of stresses and displacement were within the clinicophysiological range in all groups.The embedded region of micro-implant and the cortical bone were stress-focused areas.The changes of Von-mises stress,stretching stress and compressive stress were largely the same; the stress distribution had a decreasing tendency.Under retentive force,the stresses of group 0° and 45° were smaller than those of the other groups,with group 0° having the smallest one.The displacement of group 0° and 45° were evidently larger than those of group 90°,135° and 180°,with that of group 90° having the smallest one.Conclusion:The micro-implant embedded with different directions can safely bear 200 g force parallel to the surface of bone in embedded region.When choose the embedding directions of micro-implant,efforts should be made to reduce the retentive effect of the loaded force to keep the stability of micro-implant. |
| Key words: dentalimplants finite element analysis biomechanics embedding direction |
