虚拟牙齿矫正中牙龈变形的仿真研究

摘要

研究虚拟牙齿矫正系统,牙龈变形是开发虚拟牙齿矫正系统一个重要部分.传统的质点-弹簧模型无法实现抗弯曲变形效果,因此建立一种既能仿真拉伸变形又能实现抗弯曲变形效果的物理模型成为牙龈变形过程中亟待解决的难题.在分析质点-弹簧模型的基础上,提出并建立了一种针对软组织面模型变形的力学模型,用来解决牙龈变形问题.实验将变形的动态过程离散化,用迭代的方法求出所有牙龈质点变形的位移量.随着牙齿一步一步移动,用STL( Stereo Lithographic)文件构成的模型是由不规则三角面片组成的特点,绘制出一系列牙龈变形图像.实验结果表明方法有效,仿真效果逼真,适用于小范围移动的牙齿矫正手术方案参考.%Simulating gum deformation is a very important problem in virtual orthodontics treatment system. It is difficult to build a model which can simulate the push, stretch and bending results for STL file model composed of irregular triangles. A force model for soft tissue surface deformation was established to solve gum deformation problem based on the analysis of mass-spring model. Iterative procedure was applied to obtain displacements of all gum ver-texes by discreteing deformation process. A series of frames of gum deformation were obtained with teeth moving. Experiments show that the method is effective, and the simulation is realistic, which is suitable for micro tooth moving in correction procedure.