Intracanal cryotherapy and postoperative pain relief in symptomatic apical periodontitis: a systematic review and meta-analysis

Abstract

Postoperative pain remains a frequent complication following nonsurgical root canal treatment and is particularly associated with inflammatory pulpal and periapical conditions. Intracanal cryotherapy has been proposed as a simple and biologically plausible adjunctive strategy aimed at reducing periradicular inflammation and postoperative discomfort through localized cooling. This systematic review and meta analysis to systematically evaluate and quantitatively synthesize evidence from randomized controlled trials assessing the effectiveness of intracanal cryotherapy in reducing postoperative pain following nonsurgical root canal treatment in patients with symptomatic apical periodontitis. A comprehensive electronic search of PubMed/MEDLINE, Scopus, Web of Science, and the Cochrane Library was conducted from database inception to January 2026. Randomized controlled trials comparing intracanal cryotherapy with conventional irrigation protocols were included. The primary outcome was postoperative pain intensity measured using validated pain scales at predefined time intervals. Risk of bias was assessed using the Cochrane Risk of Bias 2 tool. A random-effects meta-analysis was conducted to estimate pooled standardized mean differences (SMDs) with 95% confidence intervals. Statistical heterogeneity was assessed using the I² statistic. Eleven randomized controlled trials were included in the qualitative synthesis, of which a subset contributed to the quantitative meta-analysis depending on the postoperative time point evaluated. Meta-analysis demonstrated that intracanal cryotherapy significantly reduced postoperative pain compared with the control intervention at 6, 24, 48, and 72 h postoperatively, whereas no statistically significant difference was observed at 12 h. Subgroup analyses based on pulpal diagnosis, tooth type, and visit protocol demonstrated consistent treatment benefits, with no significant subgroup differences. Overall, one study was judged to have a low risk of bias, one had a high risk of bias, and nine had some concerns. Intracanal cryotherapy may reduce short-term postoperative pain following nonsurgical root canal treatment in symptomatic apical periodontitis. Although current evidence supports its short-term analgesic benefit, variability in clinical protocols and moderate risk of bias among included trials warrant cautious interpretation. Further high-quality multicenter randomized controlled trials with standardized methodologies are required to strengthen clinical recommendations.

The authors' abstract, as published at the source. Scientific Reports, 2026 · DOI ↗