Restor Dent Endod.  2023 Nov;48(4):e37. 10.5395/rde.2023.48.e37.

Disinfectant effectiveness of chlorhexidine gel compared to sodium hypochlorite: a systematic review with meta-analysis

• Weissheimer T
• Pinto KP
• Silva EJNLd
• Hashizume LN
• Rosa RAd
• Só MVR

• KMID: 2548758
• DOI: http://doi.org/10.5395/rde.2023.48.e37

Abstract

This study aimed to compare the disinfectant ability of chlorhexidine (CHX) gel and sodium hypochlorite (NaOCl). Systematic searches were conducted from inception until December 8th, 2022 (MEDLINE/PubMed, Cochrane Library, Web of Science, Scopus, Embase, and Grey Literature databases). Only randomized clinical trials were included. The revised Cochrane risk of bias tools for randomized trials were used to assess the quality of studies. Meta-analyses were performed. The overall quality of evidence was assessed through the Grading of Recommendations Assessment, Development, and Evaluation tool. Six studies were included. Five had a low risk of bias and 1 had some concerns. Three studies assessed bacterial reduction. Two were included in the meta-analysis for bacterial reduction (mean difference, 75.03 [confidence interval, CI, −271.15, 421.22], p = 0.67; I² = 74%); and 3 in the meta-analysis for cultivable bacteria after chemomechanical preparation (odds ratio, 1.03 [CI, 0.20, 5.31], p = 0.98; I² = 49%). Five studies assessed endotoxin reduction. Three were included in a meta-analysis (mean difference, 20.59 [CI, −36.41, 77.59], p = 0.48; I² = 74%). There seems to be no difference in the disinfectant ability of CHX gel and NaOCl, but further research is necessary.

Keyword

Bacteria; Chlorhexidine; Endotoxin; Sodium hypochlorite; Systematic review

Figure

• 

  Figure 1 Flow diagram of the systematic search according to Preferred Reporting Items for Systematic Review and Meta-Analysis (PRISMA) guidelines.

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  Figure 2 Quality assessment of the included studies according to the Cochrane Collaboration common scheme for bias and RoB 2 tool.

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  Figure 3 Meta-analysis results. (A) Forest plot of bacterial reduction after chemomechanical preparation with chlorhexidine gel and sodium hypochlorite; (B) Forest plot of cultivable bacteria after chemomechanical preparation with chlorhexidine gel and sodium hypochlorite; (C) Forest plot of cultivable bacteria after sensitivity analysis that excluded values from Xavier et al. [46]; (D) Forest plot of endotoxin reduction after chemomechanical preparation with chlorhexidine gel and sodium hypochlorite; (E) Forest plot of endotoxin reduction after sensitivity analysis that considered only studies that performed root canal treatments.CHX, chlorhexidine; NaOCl, sodium hypochlorite; SD, standard deviation; CI, confidence interval.

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