Lewis A J
J Prosthet Dent. 1978 Feb;39(2):147-9. doi: 10.1016/s0022-3913(78)80011-0.
The fracture of removable partial denture castings does not occur in a random manner but rather at characteristic sites that are determined by the designs of the castings. These sites will be located where elastic stresses resulting either from handling or from normal function are likely to be concentrated. Regions of abrupt change in cross-sectional areas and internal voids also have been shown to cause stress concentration. In many instances the regions of stress concentration that are present may act as sites for crack initiation, with fatigue as the ultimate mode of failure.
可摘局部义齿铸件的断裂并非随机发生，而是发生在由铸件设计所决定的特征部位。这些部位将位于因操作或正常功能而产生的弹性应力可能集中的地方。横截面面积突然变化的区域和内部空隙也已被证明会导致应力集中。在许多情况下，存在的应力集中区域可能成为裂纹起始的部位，最终以疲劳作为失效模式。
