有限元应力分析不同桩核修复上中切牙牙冠的斜型缺损  

Fiber post-core restoration for incisor crown defects: Finite element analysis of stress

作　　者：杰恩斯[1] 史力[2] 

机构地区：[1]北京大学口腔医学院第二门诊部,北京市100101 [2]清华大学核研究院,北京市100084

出　　处：《中国组织工程研究》2013年第38期6717-6724,共8页Chinese Journal of Tissue Engineering Research

基　　金：北京大学口腔医院第二门诊2009科研立项项目~~

摘　　要：背景:采用纤维桩树脂核修复上中切牙近中或远中缺损可达到与牙本质接近的弹性模量,并可实现良好的美学效果,但当牙体组织大量缺损无法制备出完整的牙本质肩领时,使用纤维桩树脂核修复后桩核脱落、折断的可能性增大。目的:通过三维有限元法对比分析分别采用镍铬铸造桩核、金钯铸造桩核及纤维桩树脂核修复牙冠近远中斜行缺损后的应力分布状态。方法:挑选一颗牙体完好无损及解剖值符合中国牙体解剖平均数据的成人离体上中切牙,使用牙科专用锥形束CT扫描后,应用ABAQUS软件根据牙冠和牙本质肩领近远中斜行缺损量逆向建立牙冠斜型缺损类型的牙体-纤维桩核(镍铬桩核或金钯桩核)-全瓷冠的三维有限元模型,该模型牙冠近远中斜行缺损,牙本质肩领部分缺失;分别采用镍铬铸造桩核、金钯铸造桩核及纤维桩树脂核修复后,使用ABAQUS进行三维有限元分析,对比加载后的应力分布状态。结果与结论:上颌中切牙牙冠近远中斜形缺损,使用纤维桩树脂核修复时粘接剂层面和桩层面上的应力峰值明显低于使用镍铬或金钯桩核修复时的情况,说明牙本质肩领部分缺失的牙冠近远中斜行缺损使用金钯桩核,镍铬桩核牙根折断的可能性增大;3种桩核修复模型后牙本质层面的应力峰值基本一致。结果表明牙本质肩领部分缺失的牙冠近远中斜行缺损使用纤维桩树脂核修复效果最佳。BACKGROUND：The combination of fiber post and resin core for restorations of mesial or distal defects of the maxil ary central incisor can restore the elastic modulus close to the nature dentin, and achieve good aesthetic effects. However, when a complete dentin col ar cannot be prepared due to a large number of dental tissue defects, the post and core are easy to be lost or fractured after defect repair using the combination of fiber post and resin core. OBJECTIVE：To compare the stress distribution after nickel-chromium cast post and core, gold-pal adium cast post and core, and fiber post and resin core were used for restorations of mesial or distal defects of the maxil ary central incisors using three-dimensional finite element analysis. METHODS：An intact adult maxil ary central incisor that meets the average dental anatomical value in China was selected and scanned using a dental cone-beam CT. Then, three-dimensional tooth-fiber post and core （nickel-chromium cast post and core or gold-pal adium cast post and core）-al-ceramic crown models of mesial or distal defects of the maxil ary central incisors and part loss of dentin col ar were established using ABAQUS analysis. After repair with nickel-chromium cast post and core, gold-pal adium cast post and core, and fiber post and resin core, stress distribution in the loaded state was compared using the ABAQUS three-dimensional finite element analysis. RESULTS AND CONCLUSION：The stress peak at the adhesive and cast layers in the fiber post and resin core group was significantly lower than that in the nickel-chromium cast post and core or gold-pal adium cast post and core group. It indicated that the tooth root was easy to be fractured after mesial or distal defects of the maxil ary central incisors with partial loss of dentin col ar were restored with nickel-chromium cast post and core, gold-pal adium cast post and core. In addition, the stress peaks at the dentin layer were consistent for fiber post and core, nickel-chromium cast post and core, an

关 键 词：生物材料 组织工程口腔材料 镍铬铸造桩核 金钯铸造桩核 纤维桩树脂核 生物力学 有限元分析 牙本质肩领 应力 玻璃纤维桩 其他基金 

分 类 号：R318[医药卫生—生物医学工程]