EFFECTIVENESS OF IRRIGANTS IN ROOT CANAL DISINFECTION: SODIUM HYPOCHLORITE AND CHLORHEXIDINE – A NARRATIVE REVIEW

Abstract

This article compared sodium hypochlorite (NaOCl) and chlorhexidine (CHX) as root canal irrigants, considering their antimicrobial effectiveness, physicochemical properties, biological effects and clinical limitations. This is a narrative literature review based on searches in the Virtual Health Library and SciELO for studies published between 2018 and 2026. NaOCl stands out for its ability to dissolve organic matter, whereas CHX has substantivity but does not dissolve organic tissue. Systematic reviews and clinical studies showed no consistent difference between the solutions in microbial reduction, postoperative pain or periapical healing, and laboratory studies reported divergent results that depended on concentration, microorganism, assessment method and irrigation protocol. The literature also points to cytotoxicity, possible changes in dentin, difficulty in reaching complex anatomical areas and the formation of a precipitate when the solutions come into direct contact. It is concluded that NaOCl and CHX have distinct roles and are not interchangeable, and that the choice of irrigant should consider clinical objectives, biological safety and compatibility between agents.