桩影响前牙烤瓷冠修复后牙本质应力分布的三维有限元分析  

Analysis of Post on Dentinal Stress of Maxillary Central Incisor Restored with PFM Crown with Three dimensional Finite Element Method

作　　者：唐高妍[1,2] 文志红[1,2] 巢永烈[1,2] 樊瑜波[1,2] 

机构地区：[1]华西医科大学口腔医学院 [2]四川联合大学土木力学系生物力学所

出　　处：《华西口腔医学杂志》1998年第3期256-258,286,共4页West China Journal of Stomatology

摘　　要：采用三维有限元法分析桩对上颌中切牙金属烤瓷冠修复后牙本质应力分布的影响。选择一标准的上颌中切牙，经包埋、螺旋ＣＴ扫描、图形数字化，采用ＳｕｐｅｒＳＡＰ有限元分析软件在微机上建立三维有限元模型，模拟了牙槽骨、牙周膜、牙本质、桩、金属烤瓷冠的金属帽状冠及烤瓷层等结构，与临床实际结构类似。分别分析ＳＤＡ－Ⅱ型中熔合金桩修复前后，牙本质应力分布情况。结果表明：金属桩可改变牙本质原有的应力分布模式，使桩与牙本质交界区应力值增大；但与此同时又降低了牙本质应力峰值，Ｖｏｎｍｉｓｅｓ应力降低１３．９８％，最大主应力降低７．０５％。即从力学角度提示：合理桩修复可防止牙体断裂。The purpose of the study was to know how the posts affected the dentinal stress distribution of maxillary central incisor restored with porcelain fused to metal crown(PFM)by using the three dimension finite element method. A selected standard maxillary incisor was embedded with resin,sectioned transversely with spiral CT,and photographs made of these cross sections were digitized. Finally a three dimentsion finite element model which consisted of alveolar bone, periodontal membrane,dentin, SDA Ⅱ alloy post and PFM similar to the clinical structure was constructed by use of Super SAP(93rd edition)on a personal computer,and then the dentinal stress distribution were analyzed before and after post installation. The results showed that when subjected to masticatory loading,the post restoration changed the pattern of dentinal stress distribution with increasing the area of high stress distribution in dentin, but decreased the peak stress of dentin(Von mises stress was reduced 13 9%,maximum principle stress was reduced 7 05%). Such mechanical analysis results suggest that rational post restoration prevents teeth from fracture.

关 键 词：牙应力 核桩 烤瓷冠 三维有限元法 牙本质 PFM 

分 类 号：R783.3[医药卫生—口腔医学] R318.01[医药卫生—临床医学]