Major results of controlled clinical studies on the use of chlorhexidine in the success of endodontic treatment: a concise systematic review

Introduction: The efficacy of endodontic treatment is directly related to the elimination of bacteria. In the context of disinfection, sodium hypochlorite (NaOCl) and chlorhexidine digluconate (CHX) are recommended as irrigating solutions for the chemical-mechanical preparation of the root canal due to their broad-spectrum antimicrobial efficacy. Objective: This study aimed to develop a systematic review that addresses the main comparative clinical results of using chlorhexidine in the success of endodontic treatment. Methods: The systematic review rules of the PRISMA Platform were followed. The research was carried out from March to April 2025 in Scopus, Embase, PubMed, Science Direct, Scielo, and Google Scholar databases. The quality of the studies was based on the GRADE instrument and the risk of bias was analyzed according to the Cochrane instrument. Results and Conclusion: A total of 176 articles were found, 36 articles were evaluated in full and 11 were included and developed in this systematic review study. Considering the Cochrane tool for risk of bias, the overall assessment resulted in 27 studies with a high risk of bias and 33 studies that did not meet GRADE and AMSTAR-2. It was concluded that most randomized controlled clinical trials showed that chlorhexidine effectively reduces bacterial load, with greater reductions associated with successful outcomes. Chlorhexidine 2% is effective for clinical and radiographic success and for antimicrobial activity in primary teeth undergoing pulpectomy. Nonsurgical root canal retreatment using foraminal enlargement and 2% chlorhexidine gel demonstrated high success rates. A relatively favorable impact of chlorhexidine on post-endodontic pain was observed, with significant therapeutic implications.