EFFICACY OF DIFFERENT IRRIGATING SOLUTIONS IN ROOT CANAL DECONTAMINATION: A NARRATIVE LITERATURE REVIEW

Abstract

Decontamination of the root canal system is decisive for the success of endodontic treatment, and chemical irrigation complements mechanical instrumentation, which cannot reach the entire anatomical complexity of the root canal. This study aimed to analyze, through a narrative literature review, the evidence on differences in root canal decontamination efficacy among the main irrigating solutions. The search was carried out in the Virtual Health Library (BVS) in April 2026, using DeCS/MeSH descriptors related to root canal irrigants, decontamination, anti-infective agents and biofilms, considering publications from 2021 to 2026 in English, Portuguese and Spanish. Of the 94 records identified, 24 were read in full and 14 studies were included, two of which were classic studies obtained by manual search. The results indicate that sodium hypochlorite remains the reference irrigant, as it combines antimicrobial action with the dissolution of organic tissue and of the biofilm matrix, although it shows higher cytotoxicity. Chlorhexidine 2% shows comparable efficacy in many laboratory models, in addition to substantivity, but does not dissolve tissue and performs worse against mature multispecies biofilms. EDTA acts as a complement in smear layer removal, and combined and sequential protocols showed the best results. Alternative agents, such as chlorine dioxide, PHMB, the DJK-5 peptide and natural solutions, are promising but supported by predominantly laboratory evidence. It is concluded that the rational combination of irrigants, respecting their chemical interactions, is the most effective strategy, and clinical trials are needed to confirm these findings.