Begg技术压低切牙时牙槽骨应力分布

Analysis of the stress distribution on alveolar bone under the intrusive force system produced by Begg appliance on incisors

目的：研究Ｂｅｇｇ技术Ⅰ期切牙压低力系统作用下，牙槽骨上的应力分布，为临床正确使用Ｂｅｇｇ矫治器压低切牙提供力学参考。方法：在运用几何分析的方法研究力系统中几个典型合力分布方向基础上，应用光弹的方法直接显示这些力作用下牙槽骨上的应力分布。结果：随合力方向的改变，光弹模型中牙槽骨的应力分布不断变化。结论：Ｂｅｇｇ技术Ⅰ期弓丝支抗力和Ⅱ类牵引力的合力决定了牙齿的压低移动，应用光弹分析显示牙槽骨应力分布，可以分析牙齿的移动趋势。

Objective: To study the stress distribution on alveolar bone under the intrusive force system produced by Begg stage Ⅰ appliance on incisors. Methods:The stress distribution on alveolar bone under the combined intrusive force in different directions produced by Begg stage Ⅰ appliance was studied with geometric analysis and visualized with photoelastic stress analysis.Results:The stress distribution varied following the changes of the intrusive force direction.Conclusion:The tooth intsusive movement is caused by the combination of Begg Ⅰ stage archwire anchorage force and class Ⅱ elastic force. The teeth movement may be predicted because of the stress distribution on alveolar bone visualized with photoelastic analysis.