不同垫底材料用于聚合瓷嵌体修复后牙体组织应力变化的研究  

Analysis in the Tooth Tissue Repaired of Polymerized Porcelain Onlay with Different Base Materials

作　　者：吕越 陈晓敏 LYU Yue;CHEN Xiaomin(Department of Stomatology,Suzhou Kowloon Hospital,Shanghai JiaoTong University School of Medicine,Suzhou 215080,Jiangsu,China)

机构地区：[1]上海交通大学医学院苏州九龙医院口腔科,江苏苏州215000

出　　处：《中国美容医学》2023年第4期61-66,共6页Chinese Journal of Aesthetic Medicine

基　　金：苏州市“科教兴卫”青年科技项目(编号:KJXW2017079)。

摘　　要：目的:建立下颌第一恒磨牙聚合瓷嵌体修复后的三维有限元模型,分析不同垫底材料的厚度及弹性模量对基牙牙体组织应力分布的影响。方法:应用锥形束CT数据,建立下颌第一恒磨牙三维有限元模型。采用临床常用的6种弹性模量不同材料:光固化玻璃离子、流体树脂、高强度玻璃离子、后牙大块树脂、化学固化玻璃离子和后牙树脂,分别设定0.5 mm、1 mm、1.5 mm的厚度垫底,施加垂直向150 N、垂直向300 N、斜向150 N的静止载荷模拟不同生理咬合状态。计算并分析各组在不同载荷下基牙牙体组织各部分的应力分布情况,比较应力集中部位、等效应力及最大主应力的差异。结果:聚合瓷嵌体修复后的牙体组织内应力主要分布于牙釉质的颈部边缘处、牙本质的龈壁处及垫底层内。随着垫底材料弹性模量逐渐接近牙本质,牙釉质中的应力呈下降趋势,垫底层的应力呈增高趋势,牙本质中的应力变化趋势不明显。随垫底材料厚度增加,牙釉质颈部边缘处的应力升高,垫底层内的应力降低,牙本质中的应力变化趋势不明显。结论:选择弹性模量接近牙本质的材料进行适宜厚度地垫底,有利于应力在剩余牙体组织中的稳定传导,提高聚合瓷嵌体修复的远期成功率。Objective To investigate the biomechanical effect changes with different type and thickness of base materials after polymerized porcelain onlay restoration for mandibular first molar by finite element stress analysis.Methods The model of the mandibular first molar restored with polymerized porcelain onlay was constructed based on CT data.Six types of different elastic modulus of base materials was adopted:light cure glass ionomer,flowable composite resin,high strength glass ionomer,posterior bulk resin,chemical glass ionomer and posterior resin,setting the thickness as 0.5 mm,1.0 mm and 1.5 mm.The model was applied with static load of 150 N in vertical direction,300 N in vertical direction and 150 N in oblique direction,respectively,stimulating different occlusal states.The stresses changes on different parts of tooth tissue were calculated and analyzed by three-dimensional finite element analysis.Results The stress distribution in tooth tissue mainly focused on the neckline edge of enamel,the area towards gingival of dentin and the base layer.As the modulus of base material approaching to dentin,the stress distribution showed a downward trend in enamel,an upward trend in base layer and no significant change in dentin.As the thickness of base material increased,the stress distribution showed a downward trend in both enamel and base layer,no significant change has been detected in dentin.Conclusion Choice suitable thickness base material which was modulus similar to dentin in favour of stress stable conduction in the remaining dental tissue,and improved the long-term success rate of polymerized porcelain restoration.

关 键 词：有限元分析 高嵌体 应力分布 弹性模量 垫底材料 聚合瓷 

分 类 号：R783.1[医药卫生—口腔医学]