Objective: This systematic review aimed to evaluate the comparative efficacy of gel-based versus solution-based formulations during root canal shaping in terms of smear layer and debris removal, instrument separation, file fatigue, bacterial reduction, debris extrusion, and postoperative pain.
Methods: Following PRISMA 2020 guidelines, a comprehensive search of five electronic databases (PubMed, Scopus, Web of Science, Lilacs, and Google Scholar) and grey literature sources was conducted up to February 2025. The inclusion criteria encompassed randomized controlled trials, in vitro, ex vivo, and clinical studies that compared gel-based formulations (e.g., EDTA gel, NaOCl gel) with solution-based counterparts (e.g., NaOCl, EDTA, CHX) during root canal shaping. A total of 37 studies were included after screening and full text assessment. Data extraction focused on defined outcomes, and a narrative synthesis was performed due to study heterogeneity.
Results: Gel-based formulations demonstrated benefits such as improved glide path establishment and reduced apical extrusion. However, they were associated with several drawbacks, including increased dentinal debris retention, higher instrument fatigue, and an elevated risk of file separation, attributed to the formation of dense colloidal debris. Antimicrobial efficacy and tissue dissolution capacity were found to be inferior compared to irrigants. There was no significant advantage of gels in reducing postoperative pain. Irrigants provided superior smear removal and were more effective in minimizing bacterial load and improving push out bond strength. The included studies showed considerable variability in protocols and outcome measures, limiting direct comparisons.
Conclusion: Although gel-based formulations offer some procedural advantages, their overall clinical performance is inferior to irrigants, particularly concerning cleaning efficacy, instrument safety, and antimicrobial action. Their routine use during root canal shaping should be approached with caution and ideally followed by thorough irrigation. Further well-designed clinical trials are required to establish standardized protocols and clarify the potential role of gels in endodontic irrigation. (EEJ-2024-11-169)