有限元分析上颌中切牙唇、舌向斜形缺损后纤维桩核冠修复三维模型的应力分布  

Stress distribution of the three-dimensional post-crown model with labial and lingual oblique defects of the maxillary central incisor: a finite element analysis

作　　者：蔡跃 黄英 张慧 郭玲 Cai Yue;Huang Ying;Zhang Hui;Guo Ling(Affiliated Stomatological Hospital of Southwest Medical University, Luzhou 646000, Sichuan Province, China)

机构地区：[1]西南医科大学附属口腔医院,四川省泸州市646000

出　　处：《中国组织工程研究》2017年第30期4824-4830,共7页Chinese Journal of Tissue Engineering Research

基　　金：四川省科技计划项目(2017JY0111):钛表面N-乙酰半胱氨酸自组装膜的构建;功效及机制研究~~

摘　　要：背景:临床上牙本质肩领对桩核冠修复体的抗力和固位及边缘密封性有着重大作用。目的:采用有限元分析唇、舌向斜形缺损上颌中切牙纤维桩-树脂核-全瓷冠三维模型的应力分布。方法:挑选1颗标准离体人上颌中切牙,使用锥形束CT扫描后,导入Mimics17软件,利用CAD、UG软件构建出唇侧、舌侧肩领有缺损的桩核冠模型,分别假设唇侧或舌侧断端低,肩领有缺损,限定缺损侧肩领为0 mm,按照唇侧肩领高度-舌侧肩领高度进行分组(0 mm-0 mm、0 mm-0.5 mm、0 mm-1.0 mm、0 mm-1.5 mm、0 mm-2.0 mm、0.5 mm-0 mm、1.0 mm-0 mm、1.5 mm-0 mm、2.0 mm-0 mm、0.5 mm-0.5 mm、1.0 mm-1.0 mm、1.5 mm-1.5 mm、2.0 mm-2.0 mm),在全瓷冠切1/3、中1/3交界处,施加与牙长轴成45°的100 N静载荷力,采用有限元分析根尖部牙本质及纤维桩的Von Mises应力分布。结果与结论:①根尖部牙本质应力分布:在唇、舌侧肩领均完整的情况下,随着肩领高度的增加,牙根部Von Mises应力从集中于颈部的趋势逐渐变得更分散均匀,峰值应力随肩领高度增加而逐渐减小。在牙本质肩领有缺损的条件下,无论是舌侧或唇侧有肩领的情况下,牙根部Von Mises应力峰值较无牙本质肩领的情况有所减小,但同等高度下,舌侧有牙本质肩领组应力峰值减小更为明显,接近牙本质肩领完整组;②纤维桩应力分布:在唇、舌侧肩领均完整的情况下,随着肩领高度的增加,纤维桩Von Mises应力峰值逐渐减小。在牙本质肩领有缺损的条件下,无论是舌侧或唇侧有肩领的情况下,纤维桩Von Mises应力峰值较无牙本质肩领的情况均有所减小,但唇侧有牙本质肩领组应力峰值减小比舌侧肩领组更为明显;③结果表明:舌侧肩领对减小根部牙体应力集中较唇侧肩领明显,舌侧肩领高度有利于增强牙体抗力;唇侧肩领对减小纤维桩和粘接剂层的峰值应力较舌侧肩领明显,唇侧肩领高度有利于增加纤维桩BACKGROUND:Clinically,dentin ferrule has great influence on resistance,retention and edge sealing of post-core crowns.OBJECTIVE:To analyze the stress distribution of a three-dimensional post-crown model with labial and lingual oblique defects of the maxillary central incisor by finite element analysis.METHODS:A standard maxillary central incisor was selected and scanned by cone beam CT,and then,scanning data were imported to Mimics17software.The CAD and UG software were used to construct the post-crown model with labial and lingual oblique defects.The dentin ferrule height of the defective side was designed to be0mm,and according to the dentin ferrule height at labial side-the dentin ferrule height at lingual side,there were the following groups:0mm-0mm,0mm-0.5mm,0mm-1.0mm,0mm-1.5mm,0mm-2.0mm,0.5mm-0mm,1.0mm-0mm,1.5mm-0mm,2.0mm-0mm,0.5mm-0.5mm,1.0mm-1.0mm,1.5mm-1.5mm,2.0mm-2.0mm).In the crown cut1/3,1/3at the junction,the Von Mises stress distribution of the root dentin and fiber post was analyzed by finite element analysis using a force of100N at45°to the long axis of the tooth RESULTS AND CONCLUSION:(1)Root dentin stress distribution:In the case that the dentin ferrule at both labial and lingual sides was complete,with the increasing of the dentin height,the root Von Mises stress from the focus on the neck gradually became more evenly distributed and the peak stress gradually decreased.In the case of defective dentin ferrule,the peak of the Von Mises stress which had the dentin ferrule at the lingual side or the labial side was lower than that without the dentin ferrule,but at the same height,the dentin ferrule’s stress reduction at the lingual side was more obvious,close to the dentin ferrule ferrule complete group.(2)Fiber post stress distribution:in the case that the dentin ferrule at both labial and lingual sides was complete,with the increasing of the dentin height,fiber post’s Von Mises stress was gradually reduced.In the case of defective dentin ferrule,fiber post’s Von Mises stress which had dent

关 键 词：生物材料 口腔生物材料 纤维桩 全瓷冠 上颌中切牙 牙本质肩领 牙体缺损 VonMises应力 三维有限元 

分 类 号：R318[医药卫生—生物医学工程]