Is continuous soft chelation protocol more efficacious than conventional irrigation protocol in removing the smear...

The purpose of this systematic review is to compare the effectiveness of continuous soft chelation and conventional irrigation in removing the smear layer during endodontic treatment.

Two reviewers independently carried out an extensive literature search. Following Preferred Reporting Items for Systematic Review and Meta-Analysis guidelines; PubMed/ MEDLINE, Google Scholar, and Cochrane were searched from 2000 to 2024. In vitro studies comparing continuous and conventional chelation in smear layer removal were included. Nine studies met the criteria.

Out of 7097 articles, nine were included. Continuous chelation showed better smear layer removal in four studies, while one study favored conventional irrigation. Four studies reported similar outcomes. Etidronic acid, a soft chelating agent, was commonly used, either alone or in combination with sodium hypochlorite (NaOCl). Variations existed in protocols and outcomes. There was low-certainty evidence that continuous soft chelation protocol is better in removing the smear layer than conventional irrigation protocol. This suggests that combining a weak chelator with NaOCl solution may produce a single irrigation solution mixture that has the ability to dissolve soft tissue, has antibacterial properties, and has the ability to chelate.

Hence, continuous chelation shows promise as an alternative to conventional irrigation in smear layer removal, but more research is needed to validate findings and address methodological heterogeneity.