【摘要】 本文应用三维有限元分析了牙周膜的应力分布。重点讨论了根尖区应力分析结果及其对临床解释病因及对诊断的意义。本文将右下第一恒磨牙有限元模型划分为210个单元及1612个节点(用20节点等参元),分析了11种典型受力状况,得出以下结论:(1)在(牙合)面上通过牙周膜几何中心的各种外力在根尖区产生的应力分布均匀,且应力值较小,无拉应力产生;(2)在计算的11种典型载荷中有三种载荷应力分布危害性最大。更多还原

【Abstract】 Three-dimensional finite element analysis is used to determine the physiological stress values in the periodontal ligament (PDL). Compared with the elastic modulus E of PDL, the E of dentin and bone .are much larger. For the estimation of the stresses in PDL, the tooth and the supporting bone can be considered to be rigid. The finite element modei of PDL of the mandibular right first molar consists of 210 elements (20-node isoparametric element) and 1612 nodes.Eleven load cases were selected- in the study, which included the longitudinal occlusive load, buccal-lingual lateral load, mesial-distal lateral load and other load cases that attempted to simula-te the actual occlusive loads.The results obtained from this study lead to the following conclusions:1. For the loads which go through the physiological center of the tooth, the stresses around the apical foramina are compressive and relatively small. There qre no tensile stresses.2. Among eleven load cases studied in this work, the following three load cases are most severe:a. The maxim’um tensile stress was found under misial-distal lateral load;b. The maximum compressive stress was found under longitudinal occlusive load on the buccal groove or lingual groove;c. The highest stress concentration was found under buccal-lingual lateral load.The clinical significance of the results of stress analysis has also been discussed in the paper.更多还原