Push-out Bond Strength of Sealers After Using Different Irrigation Solutions

Objective: The aim of the present investigation was to evaluate the influence of different endodontic irrigants (sodium hypochlorite (NaOCl), chlorhexidine (CHX), and ethylenediaminetetraacetic acid (EDTA)) on push-out bond strength of the obturation materials RealSeal SE and AH Plus in vitro. Method: 200 human root canals were prepared and divided them into two groups according to the root canal filling material (RealSeal SE versus AH Plus). Each group was divided into five subgroups according to the irrigation protocol (0.9% saline (control), 3% NaOCl, 3% NaOCl with saline, 17% EDTA, and 2% CHX). After obturation, roots were sliced into 1-mm discs for push-out assessment. Compressive loading was performed using a universal testing machine at a speed of 0.5 mm/min. Two-way analysis of variance and the Kruskal–Wallis test were performed for pair-wise comparisons to assess the differences between the experimental groups. Result: AH Plus exhibited a significantly higher bond strength than RealSeal SE (mean: 2.53 and 1.53 MPa, respectively; p< 0.05), except with saline alone (p> 0.05). Within the AH Plus groups, no significant differences existed between the irrigants and saline alone (p> 0.05). The bond strength of RealSeal SE with saline alone or with NaOCl and saline did not differ from that of AH Plus with saline alone (p> 0.05). However, the push-out bond strength of RealSeal SE decreased by approximately half (p< 0.05 compared with RealSeal SE with saline alone) after rinsing with NaOCl alone, EDTA, or CHX. Conclusion: Within the limitations of an in vitro investigation it can be concluded that the bond strength of RealSeal SE is highly influenced by the used irrigant.