Push - out bond strength of quartz fiber posts to root canal dentin using total-etch and self-adhesive resin cements

Abstract

The fiber-reinforced posts are advocated due to their multiple advantages in root canal treated teeth. As debonding is the main cause of fiber posts failure, different systems and procedures are developed to improve their retention into the root canals. The objective of the present study was to investigate push-out bond strengths of fiber-reinforced posts using different total-etch and self-adhesive cements. Materials and Methods: In this in vitro study, the crowns of 90 single-rooted human premolars were sectioned and the roots were treated endodontically. Following standard post space preparation, the teeth were randomly assigned into 6 groups. The fiber-reinforced posts were placed using three self-adhesive systems (RelyX Unicem, Maxcem Elite and Biscem) and three total-etch systems (NX3, Duo-Link and RelyX ARC). Three post/dentin sections (coronal, mid & apical) were obtained from each specimen with 3mm in thickness while push-out bond strength test were performed in each root. The data were subjected to two-factor ANOVA , Kruskall Wallis and Mann Whitney U tests. In this research P value is considered 0.05. Results: The total-etch or self-adhesive cement type, canal regions and their interaction significantly influenced push-out bond strength of the specimens (all: p<0.001).Bond Strength of self- adhesive cements was significantly higher than total-etch cements. Significantly higher bond strength values was observed in the apical region. Only Duo-Link and RelyX ARC cements resulted in homogenous bond strength along the roots. In total, the most and least bond strengths were noted in RelyX Unicem self-adhesive and RelyX ARC total-etch cements respectively. Conclusion: The quartz fiber-reinforced posts placed using self-adhesive cements provided higher push-out bond strengths compared to total-etch cements while total-etch cements resulted in more uniform bond strengths in different regions of root canal.