三种桩核系统修复后牙体组织抗折裂强度的体外实验研究

目的:比较纤维根管桩核系统和金属铸造桩核修复后牙体组织的抗折裂强度和折裂模式。方法:对30个离体上颌中切牙进行常规根管治疗后截除牙冠，分别用AESTHETI—PLUS纤维桩核系统、C—POST纤维桩核系统、Cr-Co铸造金属桩核进行桩核及烤瓷冠恢复外形，包埋于底座后在INSTRON测试仪上进行抗折裂强度的测试，记录试件折裂时测试机上的读数以及试件折裂的模式，应用SPSS软件进行统计分析。结果:三种桩核系统修复后的牙体组织抗折裂强度均能达到临床要求，AESTHETI—PLUS纤维桩核修复后牙体抗折裂强度高于C—POST纤维桩核系统和Cr-Co铸造金属桩核系统，后两者之间无显著差异；AESTHETI—PLUS纤维桩核和C—POST。纤维桩核系统修复后牙体的折裂模式与Cr-Co铸造金属桩核有明显的差异。结论:AESTHETI—PLUS纤维桩核系统和C—POST纤维桩核系统具有一定的临床应用前景，但其机械性能仍需进行进一步研究。

In vitro study of the fracture resistance of pulpless teeth restored with fiber post-and-core system

Objective To compare the fracture resistance and fracture modes of pulpless teeth restored with three different post-and-core systems. Methods After schedule root canal therapy of 30 extracted maxillary central incisors was performed, the crowns of these teeth were amputated, then all these teeth were restored with two kind of fiber post core-crown systems and Cr-Co cast metal post-core-crown system. All the teeth were mounted in resin blocks. Loads were applied on the samples at 130 degrees and measured with Instron universal testing machine. Results were analyzed statistically with SPSS statistical software. Results All the three different post-core-crown systems can match the clinical demands. However, the fracture pattern of cast metal post-core system is significantly different from that of the two fiber post-core systems. Conclusions Fiber post has a bright prospect in clinical use in the near future and further study of their mechanical properties is also necessary.