不同桩核系统修复离体牙根微裂纹比较研究

摘要

Objective To compare the micro cracks of isolated teeth repaired by two different post-core restorations.Methods The crowns of 30 isolated maxillary central incisors were cut off at 2 mm above the enamel-cemental junction.These teeth were divided into three groups.Group one was repaired with nickel-chromium cast posts and porcelain-fused-to-metal crowns,group two with quartz fiber posts, resin core and porcelain-fused-to-metal crowns, group three with porcelain-fused-to-metal crowns without post.The number of micro cracks were recorded under a microscope after temperature cycling test and fatigue test.Results The number of micro cracks of group one was greater than that of the group two and three.There was no significant difference in micro cracks among four surfaces of the root of the first group.Conclusion There were more micro cracks in the tested teeth repaired with nickel-chromium cast posts and porcelain-fused-to-metal crowns than those with other post core restorations.%目的 比较两种不同桩核系统修复的离体牙和无桩修复的离体牙,在冷热循环实验和疲劳实验后牙根的微裂纹情况.方法 30颗因牙周病拔除的上颌中切牙,在釉牙骨质界上2mm截去牙冠,分成3组,每组10颗牙,分别用镍铬合金铸造桩核+金属烤瓷冠(金属桩组)、石英纤维桩+树脂核+金属烤瓷冠(纤维桩组)、无桩金属烤瓷冠修复(无桩组),进行冷热循环实验和疲劳实验,显微镜下观察牙根的微裂纹数,并记录数值,使用SPSS17.0软件进行统计分析.结果 金属桩组牙根的微裂纹数大于纤维桩组和无桩组,差异具有统计学意义.金属桩组牙根四个面之间的微裂纹数差异无统计学意义.结论 金属桩核修复的离体牙牙根的微裂纹数多于纤维桩修复和无桩修复的离体牙牙根.