基于CBCT图像构建下颌第一前磨牙三维有限元模型

目的：探索基于CBCT扫描图像快速建立下颌第一前磨牙三维有限元模型的方法。方法：选用经测量基本符合中国人牙尺寸平均值的成人下颌第一前磨牙，表面处理，石蜡包埋，应用CBCT扫描技术获取层厚为0．1mm的205张离体牙断层影像，导入Mimics10．01软件获得轮廓线点云，结合Magics9．9图像处理软件，HyPerMesh网格自动划分软件，通过特定Abaqus6．10软件建立下颌第一前磨牙三维有限元模型，并对模型进行力学加载。结果：准确地建市了下颌第一前磨牙三维有限元模型，共生成8725个单元和1874个节点，所得模型具有良好的几何相似性与生物力学相似性。从应力分布来看垂直载荷下牙体出现两个应力集中区，即加载区和牙颈部，牙颈部应力值明显小于加载区。结论：采用CBCT技术与Mimics、Anesys软件相结合建模的方法快速可行，为以后进行三维有限元分析提供了精确的模利。

Three-dimensional rebuilding of a mandibular first premolar based on the digital images by CBCT.

Objective：To study the rebuilding method of a mandibular first Premolar based on the digital images by CBCT. Method：Establishment of a three-dimensional finite element model of the adult mandibular first Premolars. Mandibu- lar first Premolars consistented with the average size of human teeth were selected,surface treatment,Paraffin-embedded. CT scan to obtain the thickness of 0.1mm 205 tomography images of isolated teeth,and imported CT data into Mimicsl0.01 soft- ware to obtain the contour Point cloud,Combination of Magics 9.9 image Processing software,HyperMesh,the grid automati- cally partitioning software, the mandibular first Premolars dimensional finite element model was established through specific of Abaqus 6.10 software,and the models were tested with loading.Result：A three-dimensional finite element model of a mandibular first Premolar was accurately established,unit generated a total of 8725 units,1874 nodes.These model had the favourable similarities of geometric and biomechanics. From the stress distribution there are two stress concentration areas under vertical load, the loading area and the tooth neck,and the tooth neck stress value is significantly less than the loading area. Conclusion：The method of construct models using the CBCT technology Mimics the software Anesys software was fast feasible, which can provide precise models for further three -dimensional finite element analysis.