Evaluation Of The Bond Strength Of Different Luting Cements In Root Canal Dentin After Post Space Preparation

ObjectiveTo evaluate the bond strength of three different luting cements and 14%EDTA irrigants on dentin bond strength after post space preparation.MethodsSixty extracted sound maxillary central incisors were endodontically treated and cut transversely 2 mm coronal to the cemento-enamel junction.After post space preparation, the teeth were assigned to three groups with 20 teeth each.The teeth of three groups were cemented with 3M ESPE RelyⅩUnicem(GroupⅠ),Panavia F(GroupⅡ) and Super Bond B&C(GroupⅢ) respectively.The teeth of each group were then divided into two subgroups,one was treated with 14%EDTA for 1 min and the other with deionized water.After filled with respective luting cements,each root was serially sectioned into 6 slices of 1mm thick for or push-out tests.The bond strength of coronal, middle and apical thirds was measured separately.SPSS 16.0 Kruskal-Wallis H test and Mann-Whitney U test were used for statistical analyses.ResultIn each third of root canal,no significant difference of bond strength was found among the three different luting cement systems with the same irrigants.In the groupⅠandⅡ,the subgroup of 14%EDTA had significantly higher bond strength when compared to the subgroup of deionized water at each third(P＜0.05).The push-out bond strength in coronal third of root canal was significantly higher than that in apical third in groupⅠandⅢ.No significant difference of bond strength was found among the three thirds in groupⅡ.ConclusionThere was no significant difference of bond strength of three different luting cement systems for clinical application.Irrigation with 14%EDTA after post space preparation can significantly improve the bond strength of the self-etching and the self-adhesion luting systems.The root regions have influence on the bond strength of luting cements.