三维几何建模与仿真技术在牙颌修复中的应用

3D Geometric Modeling and Simulating for Dentition Defect Restoration

提出正常人牙颌组织从CT数据处理到目标组织几何建模及仿真设计的技术路线。将CT断层图像经过线性插值构造出三维数据场 ,分割出目标牙颌组织后 ,利用MarchingCubes算法提取牙颌组织的三角面几何模型。采用层切法重建完整的牙列咬和面 ,其层切精度达到 0 2mm。经过配准 ,实现层切法和CT扫描所得图形线框的坐标拟合。然后在PowerSHAPE中对牙列单元进行三维重建 ,形成一套易于修改、方便组合的模型库 ;最后通过编程建立了牙列缺损与修复的几何仿真系统。

The technique of geometric modeling and simulating from CT sectional images for dentition defect restoration is presented. A 3D data field is constructed out of the sectional image stack through linear interpolation, and a seeded region-growing algorithm is adopted for the objective tissue segmentation. With Marching Cubes algorithm, the triangular mesh model is reconstructed. A layer scan method is used to build occlusal surface with the precision 0 2mm. Using registration, the data from CT sectional images and the laser scan method get fitted in the same coordinate. Then 3D models for dentition defect and restoration are reconstructed in PowerSHAPE. Fnally a multimedia simulation system is developed through Visual Basic programming.