Self-perceived pain levels following irrigation with various concentrations of sodium hypochlorite solution and gels: A systematic review of randomized clinical studies

Main Article Content

Maryam Altuhafy
Ghida Askar
Luay Jabr
Zegar Zegar

Junad Khan


Background: Sodium hypochlorite, a prevalent root canal irrigation solution, valued for its antibacterial properties and tissue-dissolving abilities, varies in concentration (0.5% to 8.25%). However, its efficacy across formulations awaits systematic evaluation.
Aim: To evaluate self-perceived post-operative pain levels in a 5.25% concentration of NaOCl in gel or solution form.
Materials and Methods: An unrestricted search of indexed databases (PubMed, Embase, Scopus, Web of Science, and Cochrane) and a manual search were performed up to April 2023. Three randomized controlled trials (RCTs) compared a solution form of 5.25% NaOCl to other solution concentrations, whereas 2 RCTs compared a gel form of 5.25% NaOCl concentration to 5.25% NaOCl solution form. The risk of Bias (RoB) assessment was conducted using the Cochrane tool.
Results: A total of 5 RCTs met the inclusion criteria and were included in the review. Four RCTs used the visual analog scale (VAS), whereas 1 RCT used the numeric rating scale (NRS) to assess post-operative pain. Three RCTs had a moderate Risk of Bias (RoB), whereas 1 had a low and 1 had a high RoB.
Conclusion: Based on the current evidence the concentration of NaOCl used during irrigation did not have any effect on the post-operative pain developed regardless of the use of a gel or solution forms. Future randomized studies with standardized protocols are needed to further investigate the efficacy of NaOCl concentration on postoperative pain in endodontic treatment.

Article Details

How to Cite
Altuhafy, M., Askar, G., Jabr, L., Zegar, Z., & Khan, J. (2024). Self-perceived pain levels following irrigation with various concentrations of sodium hypochlorite solution and gels: A systematic review of randomized clinical studies. International Journal of Dental Materials, 6(1), 22–31.
Author Biographies

Maryam Altuhafy, Eastman Institute for Oral Health

Assistant Professor of Clinical Dentistry, Orofacial Pain and TMJD, Eastman Institute for Oral Health, Rochester, NY, USA.

Ghida Askar, Eastman Institute for Oral Health

Resident, Orofacial Pain and TMJD, Eastman Institute for Oral Health, Rochester, NY, USA.

Luay Jabr, Eastman Institute for Oral Health

Resident, Orthodontics and Dentofacial Orthopedics, Eastman Institute for Oral Health, Rochester, NY, USA.

Zegar Zegar, Loma Linda University

Assistant Professor of Clinical Dentistry, Endodontics, Loma Linda University, School of Dentistry, Loma Linda, CA, USA.

Junad Khan, Eastman Institute for Oral Health

5Director and Associate Professor, Orofacial Pain and TMJD, Eastman Institute for Oral Health, Rochester, NY, USA.


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