Etidronate-enhanced sodium hypochlorite irrigation in root canal therapy: A scoping review of efficacy and safety.

Background: Continuous chelation with sodium hypochlorite (NaOCl) and etidronic acid (HEDP) has been proposed for root canal irrigation. However, its efficacy and safety compared with sequential regimens remain unclear. To map evidence on the efficacy and safety of NaOCl + HEDP in root canal treatment. Materials and Methods: A scoping review was conducted according to Joanna Briggs Institute guidance and reported following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses extension for Scoping Reviews. Web of Science, Scopus, PubMed/MEDLINE, Embase, and the Virtual Health Library were searched up to October 31, 2025. Of 576 records, 10 studies were included (6 in vitro, 3 ex vivo, and 1 clinical). Data were charted on study design, irrigation protocols, comparators, antimicrobial effects, cleaning outcomes, material compatibility, biomarkers, and postoperative pain. Results: Preclinical studies showed antimicrobial activity comparable to or greater than NaOCl alone or sequential NaOCl followed by ethylenediaminetetraacetic or citric acid. Continuous chelation was associated with improved apical smear layer removal and dentinal tubule patency, particularly with sonic or ultrasonic activation. Chemical and material compatibility was generally acceptable. The only randomized clinical trial reported higher pain during the first 48 hours, but no differences in analgesic intake or later pain. Conclusions: Preclinical evidence suggests that NaOCl + HEDP may improve apical cleaning while maintaining antimicrobial activity and acceptable compatibility. However, because the evidence is predominantly laboratory-based and only one clinical trial was identified, clinical superiority and safety cannot yet be established. Further randomized clinical trials are needed.