Cleaning efficacy and bond interaction of glycine-based air polishing and glass microparticles abrasion on dentin impregnated with premixed bioceramic sealer

Purpose: To evaluate the effect of mechanical cleaning protocols, including glycine-based air polishing and abrasion with 2 % chlorhexidine gel containing glass microparticles, on the removal of premixed bioceramic sealer residues from dentin and the bond strength of a universal adhesive applied in self-etch mode. Materials and methods: Sixty bovine dentin specimens were impregnated with either AH Plus Bioceramic Sealer or Bio-C Sealer and subjected to one of three cleaning approaches: control (water-moistened cotton pellet), glycine-based air polishing (Clinpro Prophy), or 2 % chlorhexidine gel with glass microparticles (Consepsis Scrub). Residue persistence was evaluated by scanning electron microscopy (SEM). Resin tag penetration was analyzed by confocal laser scanning microscopy (CLSM). Microshear bond strength (μSBS) testing was performed using Scotchbond Universal Plus. Failure modes were classified under an optical microscope. Data were analyzed using Kruskal–Wallis/Dunn tests (residue), one-way ANOVA/Tukey (tag length), and two-way ANOVA/Tukey (μSBS), with α = 0.05. Results: Glycine-based air polishing removed sealer residues effectively, promoted extensive resin tag formation, and produced bond strength values comparable to control groups, regardless of the sealer used. The chlorhexidine–glass microparticle protocol produced greater residue persistence, reduced tag formation, and lower μSBS values. Adhesive failures predominated in the CHX-treated groups, while cohesive failures were more frequent in glycine and control groups. Conclusion: Glycine-based air polishing effectively cleaned dentin impregnated with premixed bioceramic sealers without compromising adhesive performance. In contrast, the 2 % chlorhexidine gel containing glass microparticles negatively affects dentin cleaning and bonding effectiveness. Therefore, selecting an appropriate cleaning protocol is essential to optimize adhesion after endodontic obturation.