桩核修复方法对梭形根管牙断裂强度的影响

An in vitro study of fracture strength of fusiform canal teeth restored with different post-and-core systems

目的:比较3种不同桩核修复方法对梭形根管牙断裂强度的影响。方法:30颗近期拔除的上颌中切牙根管治疗后预备成梭形,随机分为3组,每组10颗。I组行玻璃纤维桩、Luxacore树脂核和铸造全冠修复;II组根管扩大预备后行铸造镍铬桩核和铸造全冠修复;III组玻璃离子水门汀重塑根管后行铸造镍铬桩核和铸造全冠修复。Zwick z010型电子万能试验机测试断裂强度。结果:I组与II组、III组试件牙的断裂强度差异有显著性,II组与III组差异无显著性。结论:梭形根管牙的断裂强度与其修复设计有关,采用玻璃纤维桩及树脂核修复有较高的断裂强度,且断裂方式利于再修复。

Objective： To compare the fracture strength of fusiform canal teeth restored with three different post-and-core systems. Methods： Artificial fusiform canals were prepared in 30 recently extracted maxillary central incisors which had been endodontically treated and randomly divided into three group of ten each.Teeth in group-Ⅰ received glass fiber posts, Luxacore resin cores and full cast crowns. Teeth in group-Ⅱ were secondarily prepared to widen root canal and received cast Ni-Cr posts, cores and full cast crowns. Teeth in group-Ⅲ, whose fusiform canal were rehabilitated with glass ionomer cement, cast Ni-Cr posts, cores and full cast crowns. Fracture strength of all these samples were measured by the universal mechanical testing machine （Zwick z010）. Results： There were significant differences in fracture strength between group-Ⅰ and group-Ⅱ, Ⅲ and was no significant difference between group-Ⅱ and group-Ⅲ. Conclusions： The fracture strength was closely related with post-and-core system. Glass fiber post and composite resin core had high fracture strength in fusiform canal tooth and the fracture was easier to repair.