不同材料高嵌体修复大面积缺损的上颌第一前磨牙有限元分析

Finite Element Analysis of Maxillary First Premolars Repaired with Different Onlay Materials

目的:探讨4种材料高嵌体修复大面积缺损上颌第一前磨牙后,材料及牙体结构受应力大小及分布情况。方法:收集1颗完整的离体上颌第一前磨牙,通过锥形束CBCT扫描技术、Mimics19.0、Hypermesh、Ansys19.0等逆向工程软件,建立大面积缺损的上颌第一前磨牙三维有限元模型。用金合金、氧化锆、复合树脂、玻璃陶瓷四种不同材料做高嵌体修复,来观察在垂直向与侧向加载时,修复体及剩余牙体组织的所受最大主应力大小变化和分布情况。结果:对于剩余牙体组织来说,垂直加载时的最大主应力从大到小为:复合树脂>璃陶瓷瓷>氧化锆=金合金;侧向加载时为:复合树脂>氧化锆>金合金>玻璃陶瓷;对于修复材料来说,垂直加载时最大主应力从大到小为:金合金>氧化锆>玻璃陶瓷>复合树脂;侧向加载时为:氧化锆>玻璃陶瓷>复合树脂>金合金。结论:综合受力分析,大面积缺损的上颌第一前磨牙,首选玻璃陶瓷高嵌体修复,但建议减低牙尖斜度,给予适当调[牙合]。

Objective:To investigate the intensity and distribution of stress after the restoration of the first maxillary premolar with large defect by using four different materials.Methods:One normal and intact first maxillary premolar was collected.Through CBCT scanning technology,Mimics19.0,Hypermesh2017,and Ansys19.0 reverse engineering software,3D finite element model of large defects was established.Gold alloy,zirconia,composite resin,and glass-ceramic were used to restore the defect in the form of onlay.The intensity and distribution of maximum principal stress of onlay and residual dental tissues were observed when loaded vertically and laterally.Results:For the remaining tooth tissues,the order of maximum principal stress of tooth enamel under vertical loading was:composite resin>glass-ceramic>zirconia=gold alloy,the order of maximum principal stress of tooth enamel under lateral loading was:composite resin>zirconia>gold alloy>glass-ceramic.For the repair materials,the order of maximum principal stress of the onlay under vertical loading was:gold alloy>zirconia>glass-ceramic>composite resin,the order of maximum principal stress of the onlay under the lateral loading was:zirconia>glass-ceramic>composite resin>gold alloy.Conclusion:For large defects of the first maxillary premolar,the first choice is glass-ceramic onlay,however,with recommendation to reduce the inclination of the tooth tip and provide occlusal adjustment.