前牙冠折后再接修复和复合树脂直接修复剪切力的比较

Comparison of the shear bond strength between fragment reattachment and composite resin restoration for crown-fractured anterior teeth

目的:比较断冠再接和复合树脂直接修复两种方法修复前牙冠折后剪切力的差异。方法:制备恒上颌中切牙不累及髓腔的冠折模型36个,随机分为A、B组(n=18),A组采用自酸蚀粘结剂Clearfil SE Bond进行断冠再接,B组采用Clearfil SE Bond和复合树脂Clearfil AP-X进行直接修复。修复24 h后置于万能试验机加载台上,持续加载、直至折断,并记录折断时的力值。结果:断冠再接和复合树脂直接修复后的剪切力(N)分别为326.78±70.66和351.74±54.11(t=1.190,P=0.242)。结论:断冠再接和复合树脂直接修复两种方法修复前牙冠折后剪切力无明显差异。

AIM： To compare the shear bond strength of fragment reattachment and composite resin restora-tion for crown - fractured anterior teeth. METHODS ： 36 in vitro models of crown - fractured maxillary central incisor were divided into 2 groups （n = 18） randomly. The fractured crowns in group A were reattached by Clearfil SE Bond while those in group B were restored by the same adhesive and composite resin AP - X. Then the teeth were submitted to an axial compression test in a Universal Testing Machine. The spade was put on the buccal surface of the tooth verti-cally with a speed of 1 mm/min and a maximum limit of 10 kN until the tooth fractured. RESULTS ： The mean shear bond strength of group A and group B were （326.78 ±70.66）N and（351.74 ±54. 11）N respectively （t = 1. 190, P = 0. 242） . CONCLUTION ： The shear bond strength of composite resin build - up is similar to that of fragment re-attachment.