Effect of Dual Rinse HEDP on the push-out bond strength of AH Plus and AH Plus Bioceramic sealers: an in vitro study

The adhesion of root canal sealers to dentin is critical for preventing microleakage and ensuring long-term endodontic success. Irrigating agents influence dentin surface characteristics and thus affect sealer bond strength. This study aimed to compare the effects of continuous chelating (NaOCl + HEDP) and sequential chelating (NaOCl followed by EDTA) protocols on the bond strength of AH Plus and AH Plus Bioceramic root-canal sealers. Fifty-two extracted human mandibular premolars were decoronated and divided into two groups. Chemo-mechanical preparation was completed using 2.5% NaOCl (Group 1) and a mixture of 2.5% NaOCl + 9% HEDP (Dual Rinse, Group 2) up to ProTaper Next X3. Final irrigation was performed with 17% EDTA in Group 1 and 9% Dual Rinse HEDP in Group 2. Each group was further divided into two subgroups according to the sealer used: AH Plus or AH Plus Bioceramic. Root sections (1.5 mm thick) were taken from apical, middle, and coronal thirds. Bond strength was evaluated using a universal testing machine at 1 mm/min in the apico-coronal direction. Failure modes were also evaluated. Data were analysed using a three-way mixed-effects ANOVA with irrigation protocol and sealer type as between-subject factors and anatomical region as a within-subject factor, followed by post hoc comparisons based on estimated marginal means. Continuous chelation significantly increased the bond strength of AH Plus but had no effect on AH Plus Bioceramic. Cohesive failure was dominant in AH Plus, while no dominant mode was observed in AH Plus Bioceramic. Bond strength increased toward the apical region in all groups. Irrigation protocols influence the bond strength of root canal sealers. Continuous chelation may enhance adhesion, particularly for epoxy resin–based sealers, while it does not appear to significantly affect the bond strength of AH Plus Bioceramic.