Acetic acid as a final irrigant in post-space preparation enhances dentin cleaning and bonding performance compared with EDTA

de Freitas Ceccato J.; Rojas López J.A.; de Oliveira E.C.G.; Besegato J.F.; Escalante-Otárola W.G.; Kuga M.C. · International Journal of Adhesion and Adhesives (2026) · DOI: 10.1016/j.ijadhadh.2026.104315

Resumen

Purpose: To evaluate the effects of post-space irrigation protocols using 2.5% sodium hypochlorite or 6.0% calcium hypochlorite followed by 17% EDTA or 6.0% acetic acid on residue incidence, dentinal tubule openness, push-out bond strength, and failure mode of a glass fiber post cementation system. Materials and methods: Eighty bovine incisors underwent endodontic treatment and post-space preparation. Specimens were assigned to four final irrigation protocols (n = 20): SH-ED (2.5% sodium hypochlorite + 17% EDTA), SH-AA (2.5% sodium hypochlorite + 6.0% acetic acid), CH-ED (6.0% calcium hypochlorite + 17% EDTA), and CH-AA (6.0% calcium hypochlorite + 6.0% acetic acid). Residue incidence was scored on scanning electron microscopy images at 500 ×, and open dentinal tubules were quantified at 2000 × . For bonding analysis, customized glass fiber posts were cemented using a silane-containing universal adhesive (Ambar Universal Plus APS) and a conventional resin cement (AllCem Core). After 6 months of water storage, push-out bond strength was evaluated at the cervical, middle, and apical thirds, and failure modes were assessed under stereomicroscopy. Data were analyzed using Kruskal–Wallis/Dunn tests for residue incidence, one-way ANOVA/Tukey tests for bond strength, two-way ANOVA followed by Tukey's post hoc test for bond strength, and Fisher's exact test for failure mode distribution (α = 0.05). Results: Protocols complemented with 6.0% acetic acid showed lower residue incidence and a greater number of open dentinal tubules compared with EDTA-complemented protocols. Acetic acid groups exhibited significantly higher push-out bond strength values across all post-space thirds when compared with EDTA groups. Cohesive failures predominated in acetic acid protocols, whereas adhesive failures between the fiber post and cementation system were more frequent in EDTA groups. Conclusion: Post-space irrigation using sodium or calcium hypochlorite followed by 6.0% acetic acid showed superior dentin cleanliness and bonding effectiveness compared with EDTA-complemented protocols.

Instituciones: Universidad Católica de Santa María