下颌牙列直丝弓矫治器三维有限元模型的建立  

Construction of three-dimensional finite element model of straight wire appliance for mandibular dentition

作　　者：李九军[1] 张静[1] 

机构地区：[1]河南省安阳市口腔医院正畸科,安阳455000

出　　处：《口腔医学》2013年第10期653-656,共4页Stomatology

摘　　要：目的利用三维有限元建模的方法,探索建立下颌牙列直丝弓矫治器的力学分析模型。方法采用螺旋CT对个别正常的志愿者下颌骨进行多层扫描,以(医学数字成像和通讯标准)DICOM格式导入Mimics软件中,利用灰度值的差异来重建下颌骨与牙列;以.txt格式把下颌骨与牙列点云数据导入逆向工程软件Geomagic Studio 8.0中,构造三角网格面,并进行NURBS曲面拟合生成颌骨与牙齿的实体模型。然后以.igs格式导入Ansys中,在Ansys中建立直丝弓托槽和弓丝的模型,并在Geomagic中对牙根表面进行扩增0.25 mm生成牙周膜并进行布尔运算,生成牙齿、颌骨、牙周膜、托槽、弓丝的装配模型。结果建立了直丝弓矫治器三维有限元模型,在Ansys软件内对模型进行分区划分网格并施加一定的约束和载荷,即可进行三维有限元的力学分析。结论利用螺旋CT成像,并充分结合Mimics,Geomagic及Ansys软件的优点建立的直丝弓矫治器三维有限元模型精确有效,方法简单实用,可操作性强,耗时少。Objective To explore the construction of mechanical model of straight wire appliance for mandibular arch by three-di- mensional finite element modeling. Methods Scanning of images of individual madible and dentition with normal occlusion was made through muti-slice spiral CT scanner. Data were imported into Mimics software in the format of DICOM. Difference in gray values was used to reconstruct mandibular jaw and dentition. Cloud data of jaw and dentition points were imported into Geomagic Studio 8.0 in the format of . txt to construct triangular meshes. Carry out NURBS surface fitting to generate entity model of jaw and dentition. Data were imported into Ansys software in the format of. igs. Build the model of straight-wire bracket and arch wire in Ansys. In Geomagic Studio 8.0,augment root surfaces by O. 25 mm to generate the periodontal membrane, and carry out Boolean operation to generate assembly model of teeth,jaws,periodontium,brackets and wires. Results A three-dimentional finite element model of straight wire appliance was constructed. In Ansys, partition the model, divide the meshes, and impose certain constraints and loads, then mechanical analysis of three-dimensional finite element could be carried out. Conclusions Building three-dimensional finite element model of straight wire appliance by spiral CT imaging and by combing merits of Mimics, Geomagic Studio and Ansys is precise, effective, simple, practical, op- erable and less time consuming.

关 键 词：三维有限元 直丝弓矫治器 牙列 下颌骨 

分 类 号：R783.5[医药卫生—口腔医学]