不同洞型嵌体有限元模型的建立及应力分布初步探讨

Setup of finite element model of maxillary premolar with different designed MOD cavities and primary analysis of stress distribution

目的建立不同近中-牙合面-远中(MOD)洞型嵌体修复上颌前磨牙的计算机三维实体和有限元模型并进行初步应力分析。方法利用片切技术获得牙体原始图片数据,通过三维造型软件Rhino(犀牛)建立嵌体修复的上颌前磨牙三维实体模型,并导入有限元前处理软件Patran中,生成有限元模型。结果建立起包含牙釉质、本质、髓腔以及牙周膜的精细上颌前磨牙三维有限元模型;牙本质应力随嵌体窝洞宽度增大而增大,高嵌体可以改善牙体内部应力集中。结论利用片切技术可以获得较为清晰的断面扫描图片,有助于区分牙体的精细结构;三维造型软件Rhino可以直接读入二维轮廓信息,提高了建模的精度和效率,并且界面友好,易于口腔医师的掌握。

Objective To establish a 3D solid and finite element model of maxillary premolar restored with MOD inlay. Methods By means of slice technique, the original photographic data of the tooth were taken. Then the 3-D solid model of the maxillary premolar restored with inlay was set up by using Rhino software. Results A more precise 3D solid and finite element model of maxillary premolar restored with inlay was constructed, which included enamel, dentine, pulp chamber and peridentium. Conclusion Clear section pictures that help to discem tooth structure were obtained by using slice technique; Rhino software can import B-sphnes that improve the precision of the 3D model, and the software also has a friendly interface which is easy for dentists to control.