Evaluation of the impact of two irrigating solutions on postendodontic treatment pain in teeth with pulpal necrosis: A systematic review of randomized clinical trials and updates

Introduction: Some irrigating solutions have the potential to induce postendodontic treatment pain (PETP). Unfortunately, there is no clear guidance of suitable irrigating solution to contribute in reducing the PETP in the current literature. This study aimed to collect and evaluate all available updated studies that investigated the impact of sodium hypochlorite (NaOCl) against chlorhexidine (CHX) on PETP following root canal therapy in permanent teeth with pulpal necrosis. Materials and Methods: The reviewers searched PubMed, Scopus, Web of Science databases, and Google Scholar as an engine to retrieve relevant randomized clinical trials (RCTs). RCTs were done on comparing the effect of NaOCl and CHX on PETP in teeth of adult patients with pulpal necrosis. Reviews, animal studies, and other irrelevant studies were excluded. This systematic review was carried out in accordance with the preferred reporting items for systematic review and meta-analysis guidelines. The reviewers selected the articles based on specified eligibility criteria, performed data extraction, and evaluated the risk of bias. Results: Four articles met the inclusion criteria for the systematic review. Two studies were deemed to have a low risk of bias. The outcomes illustrated no statistically significant difference regarding PETP between the two irrigating solutions. Conclusions: Based on current studies, this review found that neither NaOCl nor CHX irrigating solutions could ensure the absence of PETP.