上颌中切牙斜形折裂修复设计的有限元分析  

Finite Element Analysis of Different Repairing Designs for Maxillary Central Incisor with Oblique Defect

作　　者：李茜茜 康婷 陈燕语 宋丹阳 郭玲 LI Xixi;KANG Ting;CHEN Yanyu;SONG Danyang;GUO Ling(Oral & Maxillofacial Reconstruction and Regeneration Laboratory, Southwest Medical University, Department of Prosthodontics, The Affiliated Stomatology Hospital of Southwest Medical University, Luzhou 646000, China;Department of Stomatology, the First People's Hospital of Liangshan, Liangshan 615000, China;Department of Radiology, the People's Hospital of Deyang, Deyang 618000, China;Department of Stomatology, the People's Hospital of Yaan, Yaan 625000, China)

机构地区：[1]西南医科大学口腔颌面修复重建与再生实验室,西南医科大学附属口腔医院修复科,四川泸州646000 [2]凉山彝族自治州第一人民医院口腔科,四川凉山615000 [3]德阳市人民医院放射科,四川德阳618000 [4]雅安市人民医院口腔科,四川雅安625000

出　　处：《口腔医学研究》2020年第3期259-263,共5页Journal of Oral Science Research

基　　金：四川医事卫生法治研究中心课题(编号:YF17-Y27)。

摘　　要：目的:通过三维有限元方法分析研究上颌中切牙斜形折裂采用不同方式修复后的应力分布。方法:利用CBCT及三维有限元软件,建立上颌中切牙斜形折裂的有限元模型,并对缺损牙按照3种修复方法建模,分析各组模型在侧向力下的Von Mises等效应力和最大主应力分布与峰值。结果:(1)同种折断模式下,剩余牙体组织等效应力值:纤维桩核冠组最大,5 mm髓腔固位冠组最小;修复体等效应力值:铸造桩核冠组最大,纤维桩核冠组最小;纤维桩核冠组粘结层的等效应力峰值最高。(2)随着肩领高度增加,剩余牙体组织等效应力均减小,纤维桩核冠组和铸造桩核冠组比髓腔固位冠组递减率更大;且舌侧肩领高度增加比唇侧肩领高度增加所造成的剩余牙体组织等效应力递减率更大。结论:完整且高度足够的牙本质肩领是上前牙大面积缺损时采用纤维桩核冠和铸造桩核冠修复的必要条件,当牙本质肩领不完整时,舌侧肩领比唇侧肩领更有利于提高残根的抗折性。当上颌中切牙斜形折裂,肩领不完整时,采用髓腔固位冠修复的应力分布优于桩核冠,其中固位体深度为5 mm的髓腔固位冠可能是最佳修复方式;若采用桩核冠修复,铸造桩核冠比纤维桩核冠更有利于剩余牙体组织应力均匀分布。Objective:To analyze the stress distribution of maxillary central incisor oblique fracture with different repair methods by three-dimensional finite element analysis.Methods:The finite element models of maxillary central incisor with oblique fracture were established using CBCT and finite element software.The conditions were then created according to three repair methods after root canal treatment.The Von Mises equivalent stress and maximum principal stress distribution and peak value of each model were analyzed.Results:(1)In the same kind of fracture mode,the equivalent stress value of the remaining tooth tissue was:the fiber post-core-crown group was the largest and the 5 mm deep endocrown group was the smallest.The equivalent stress value of the prosthesis was:the cast post-core-crown group was the largest and the fiber post-core-crown group was the smallest.The equivalent stress peak of the bond layer of the fiber:post-core-crown group was the highest.(2)With the increase of the height of ferrule,the equivalent stress of the remaining tooth tissues was reduced,and the reduction rate of the fiber post-core-crown group and the cast post-core-crown group was larger than that of the endocrown group.When the lingual ferrule height increased,the equivalent stress reduction rate of residual tooth tissue was greater than that of the lip ferrule height.Conclusion:Complete and high enough dentin ferrule is a requirement for repairing heavily defected maxillary central incisor with fiber post-core crown and cast post-core crown.When the dentin ferrule is incomplete,lingual ferrule is better than lip ferrule to improve the fracture resistance of residual dentin.When the maxillary central incisor obliquely fractured and the ferrule is incomplete,the stress distribution of the endocrown is more excellent than post-core-crown.And the endocrown with a depth of 5 mm retainer may be the best repair method.As for post-core crown restoration,the cast post-core crown is more favorable for the uniform distribution of residual toot

关 键 词：牙本质肩领 上颌中切牙 髓腔固位冠 桩核冠 三维有限元 

分 类 号：R78[医药卫生—口腔医学]