夹层技术不同充填材料和咬合角度对非龋性颈部缺损牙体应力分布的影响

Effects of Sandwich Technology and Occlusal Angle of Different Filling Materials on Stress Distribution of Non-caries Cervical Lesions

目的:使用三维有限元法分析运用夹层技术时不同充填材料和咬合角度对患非龋性颈部缺损的下颌第一前磨牙及充填体应力分布的影响。方法:建立下颌第一前磨牙非龋性颈部缺损三维有限元模型作为对照组,4组材料修复模型作为实验组:A组:3M Filtek Z350XT树脂-玻璃离子水门汀,B组:3M Filtek Z350XT树脂-Cention N,C组:3M Filtek Z350XT Flowable流动树脂-玻璃离子水门汀,D组:3M Filtek Z350XT Flowable流动树脂-Cention N。给予所有模型位于颊尖顶的垂直向载荷(0°)和位于颊尖偏颊侧的侧向载荷(30°、45°、60°)各100 N,用ANSYS 17.0进行应力分布分析。结果:(1)对照组侧向加载时剩余牙体组织Von Mises应力峰值(MPa)比垂直向时分别增加49.3%、222.4%、376%.与对照组相比较,A、B、C、D各组充填完成后均能大幅度地降低牙体组织应力,但组间差异不大。(2)随着载荷角度的增大,内层材料应力峰值(Mpa)由大到小依次为D组>B组>C组>A组。(3)随着载荷角度的增大,外层材料Von Mises应力峰值由大到小依次为为A组>B组>C组>D组。(4)随着载荷角度的增大,粘接剂在垂直载荷时,按Von Mises应力峰值由大到小依次为C组>D组>A组>B组,侧向载荷时,由大到小依次为A组>B组>C组>D组。结论:从结果综合来看,相同咬合状态下,使用3M Filtek Z350XT Flowable流动树脂-Cention N材料组合的夹层技术修复患有非龋性颈部缺损的下颌第一前磨牙时更具优势,此结论也许能为夹层技术修复非龋性颈部缺损材料的选择提供参考。

Objective:To analyze the effects of different filling materials and occlusal angles on the stress distribution of mandibular first premolars with non-caries cervical lesions by three-dimensional finite element method.Methods:A three-dimensional finite element model of mandibular first premolars with non-caries neck defect was established as control group.Four groups of material were used as the experimental group.Group A:3M Filtek Z350XT resin-glass ionomer cement.Group B:3M Filtek Z350XT resin-Cention N.Group C:3M Filtek Z350XT Flowable Resin-Glass ionomer Cement.Group D:3M Filtek Z350XT Flowable Resin-Cention N.All models were given a vertical load(0°)at the buccal tip and a lateral load(30°,45°,60°)at the side of the buccal tip with 100N each,and the stress distribution was analyzed using ANSYS 17.0.Results:(1)In the control group,the Von Mises stress peak value increased by 49.3%,222.4%,and 376%under lateral loading compared with vertical loading,respectively.Compared with the control group,the dental tissue stress was significantly reduced in groups A,B,C,and D after filling,but there was only slight difference among groups.(2)With the increase of load angle,the stress peak value(MPa)of inner material was D>B>C>A.(3)With the increase of loading angle,the Von Mises stress peak of the outer material was A>B>C>D.(4)With the increase of loading angle,the stress peak value(Mpa)of adhesive in vertical loading was C>D>A>B,and the order of peak Von Mises stress in lateral loading was A>B>C>D.Conclusion:3M Filtek Z350XT Flowable resin-Cention N material combination has more advantages in repairing the mandibular first premolars with non-caries cervical lesions under the same occlusion condition.