纤维桩和铸造桩修复尖牙牙体缺损后牙本质受力的三维有限元分析

摘要

Objective:To explorethe stress magnitude and distribution of canine tooth defect dentin restored by fiber post and cast post ,and provide a theoretical basis for clinical application .Methods:The maxillary canine model was set up . After the dentin was restored by glass fiber post and cast cobalt-chromium alloy post ,its stress value and distribution was analyzed by the three-dimensional finite element analysis (3D FEM ) using ANSYS .Results:After restoration of tooth defect by cast cobalt-chromium alloy post and glass fiber post ,the stress peak value of dentin at the labial side was higher than that at the lingual side .The peak value of von Mises stress was located on the root surface at 1/3 of the root neck ,and von Mises stress value showed a decreasing trend from 1/3 of the root neck to 1/3 of the root tip .The peak value of von Misesstress , tensile stress peak value and compressive stress peak value of glass fiber post were all significantly lower than those in cast cobalt-chromium alloy post(P<0 .05) .Conclusions:Three dimensional finite element analysis can better simulate the tooth stress distribution ,and glass fiber post can help relieve tensile and compressive stress of caninetooth defect and lower the risk of tooth fracture .%目的：探讨尖牙牙体缺损采用纤维桩和铸造桩修复后的牙本质应力大小及应力分布，为临床应用提供参考。方法：建立上颌尖牙模型，用ANSYS软件对铸造钴铬合金桩核、玻璃纤维桩核修复后的牙本质应力数值及分布情况进行三维有限元分析。结果：铸造钴铬合金桩与玻璃纤维桩修复牙体缺损后，牙本质的唇侧应力峰值均大于舌侧，牙本质Von Mises应力峰值均位于根颈1／3牙根表面，且Von Mises应力值从根颈1／3向根尖1／3呈递减趋势。玻璃纤维桩的Von Mises应力峰值、拉应力峰值、压应力峰值均小于铸造钴铬合金桩（P＜0．05）。结论：三维有限元分析可较好模拟牙体应力分布，玻璃纤维桩有助于缓解尖牙牙体缺损处所承受的应拉力，降低患牙折裂风险。