桩核冠修复体牙本质肩领效应的扩展有限元分析  

The influence of ferrule effect on post-restored restoration using extended finite element method

作　　者：张一祎 阿依古丽·阿不都斯木 李清[2] 王贻宁[2] 

机构地区：[1]武汉大学口腔医学院口腔基础医学省部共建国家重点实验室培育基地和口腔生物医学教育部重点实验室,430079 [2]武汉大学口腔医学院修复科,430079

出　　处：《中华口腔医学杂志》2014年第6期357-361,共5页Chinese Journal of Stomatology

基　　金：国家自然科学基金（81100784）

摘　　要：目的 利用基于断裂力学理论的扩展有限元法,探讨牙本质肩领高度对纤维桩核冠修复体应力分布及断裂失败过程的影响,以期为临床提供参考.方法 使用齿科非接触式红外扫描仪获得扫描数据,利用Simpleware软件构建上颌中切牙桩核冠修复体三维模型,分别设计牙本质肩领高度为0、1、2、3 mm的模型.使用Abaqus有限元分析软件,线性分析腭侧45°加载350 N静态载荷时修复体各结构的应力分布.利用基于断裂力学理论的扩展有限元最大主应力准则,非线性分析粘接界面破坏的发生和发展.结果 线性分析显示4种模型应力分布相近,但0和1 mm模型玻璃离子粘接剂层腭侧有明显的应力集中.非线性分析显示0 mm模型在静态载荷加载50.4和94.7 N时玻璃离子和树脂粘接剂层发生破坏.3 mm模型在静态载荷加载65.9和228.2 N时玻璃离子和树脂粘接剂层发生破坏.结论 扩展有限元可准确模拟纤维增强树脂桩核冠修复体的破坏失败过程;牙本质肩领通过减小和分散粘接界面的应力,有效保护粘接界面;增加牙本质肩领高度对提高纤维桩核冠修复体的稳定有积极意义.Objective To investigate the stress distributions and cracks initiation and propagation within the cementation of post and core restored teeth with various ferrule heights.Methods Threedimentional finite element（FE） models of post and core restored teeth with different ferrule heights（0,1,2,3 mm） were created by using the data of a three-dimentional non-contact digital scanning.Vertical oblique forces of 350 N （45 ° to the long axis of the root） were applied on the lingual surface of the teeth （4 mm below the incisal edge）.Both linear analysis and extended finite element methods （XFEM） were used to investigate stress distributions,especially those in the adhesive interfaces.Results Linear analysis results showed that the stress distributions within the root were quite similar among the groups.However,obvious stress concentrations were detected on palatal glass ionomer cement layer in the groups with 0 mm and 1 mm ferrule.According to the XFEM results,cracks were firstly initiated within the glass ionomer cement layer,and then propagated towards the adhesive resin cement layer.The ultimate loads that induced the damage within glass ionomer cement layer and adhesive resin cement layer in 0 mm ferrule group （50.4 and 94.7 N）were less than those in 3 mm ferrule group（65.9 and 228.2 N）.Conclusions Adhesive interface was the susceptible structure of post and core restored teeth.Increasing ferrule height can significantly reduced the stress concentration within the palatal adhesive interface.

关 键 词：桩核技术 有限元分析 牙修复失效 肩领 

分 类 号：R783.3[医药卫生—口腔医学]