不同材料嵌体修复对楔状缺损患牙应力分布影响的三维有限元分析

Three-dimensional finite element analysis of the effect of inlay restoration with different materials on the stress distribution of wedge-shaped defects

目的建立下颌第一前磨牙楔状缺损及不同材料嵌体修复后的三维有限元模型,并进行应力分析,以期为临床嵌体修复楔状缺损提供理论参考。方法通过CBCT扫描取得牙体原始数据,借助Mimics 17.0,Geomagic Studio 13.0等软件建立下颌第一前磨牙楔状缺损模型及三维有限元模型,并分别进行树脂嵌体(A)、瓷嵌体(B)、金合金嵌体(C)修复,以未进行修复的楔状缺损模型作为对照组,再利用Abaqus 6.14有限元软件进行牙颈部的应力分析。结果从应力分布来看垂直载荷楔状缺损后剩余牙体组织及嵌体修复后模型均出现两个应力集中区,其中楔状缺损后剩余牙体组织模型主要应力集中在楔状缺损处,嵌体修复后模型主要应力在牙颈部,并发现不同材料嵌体修复后最大主应力值均明显降低。结论不同材料嵌体修复楔状缺损后可使缺损附近的应力集中明显改善,其中瓷嵌体(B)和金合金嵌体(C)与树脂嵌体(A)相比相对理想。

Objective A three-dimensional finite element model of the mandibular first premolar wedge-shaped defect and different material inlay restorations was established, and stress analysis was carried out to provide a theoretical reference for clinical inlay restoration of wedge-shaped defects. Methods The raw data of the tooth were obtained by CBCT scanning. The wedge-shaped defect model and the three-dimensional finite element model of the mandibular first premolar were established by Mimics 17.0 and Geomagic Studio 13.0 software, and the resin inlay(A) and porcelain inlay(B) were respectively performed. The gold alloy inlay(C) was repaired, and the undefended wedge-deficient model was used as the control group, and the stress analysis of the tooth neck was performed using Abaqus 6.14 finite element software. Results From the stress distribution, there were two stress concentration areas in the residual tooth structure and the inlay restoration model after the vertical load wedge defect. The main stress of the remaining tooth body tissue model after wedge deficiency was concentrated in the wedge defect, and the inlay restoration model. The main stress was in the neck of the tooth, and it was found that the maximum principal stress values of the inlays of different materials were significantly reduced. Conclusion The inlays of different materials can repair the wedge-shaped defect and improve the stress concentration near the defect. The porcelain inlay(B) and the gold alloy inlay(C) are ideal compared with the resin inlay(A).