Effect of Antioxidants and Chelating Agents on the Bond Strength of Calcium Silicate–Based Root Canal Sealers: An In Vitro Study

Aim: This study evaluated the effects of two antioxidants (proanthocyanidin and sodium ascorbate) and two chelating agents (EDTA and glycolic acid) on the push-out bond strength of a calcium silicate–based root canal sealer to dentin. Materials and Methods: Eighty-four single-rooted mandibular premolars were decoronated to a standardized length of 13 mm. After root canal preparation and irrigation, specimens were divided into six groups according to the antioxidant and chelating agent applied. During the final irrigation protocol, chelating agents and antioxidants were used at recommended concentrations and exposure times. Root canals were then obturated using a calcium silicate–based sealer (CSBS) and gutta-percha. From each specimen, 2-mm-thick slices were obtained at 4-mm and 9-mm levels from the apex, and push-out testing was performed in the apico-coronal direction. Bond strength values (MPa) were calculated and analyzed using three-way ANOVA and Tukey post-hoc tests (p0.05). Bond strength at the 9-mm level was significantly higher than at the 4-mm level (p<0.05). Conclusion: Incorporating proanthocyanidin into the final irrigation protocol may counteract the oxidative effects of NaOCl and improve the bond strength of calcium silicate–based sealers. Glycolic acid demonstrated similar efficacy to EDTA, suggesting it could serve as a potential alternative chelating agent in endodontic practice.