Effectiveness of intracanal cryotherapy in root canal therapy: A systematic review and meta-analysis of randomized clinical trials.

Sadaf, Durre; Ahmad, Muhammad Z; Onakpoya, Igho J

INTRODUCTION The effectiveness of intracanal cryotherapy for reducing postoperative pain is unclear. The objective of this systematic review was to evaluate the effect of intracanal cryotherapy on postoperative pain after root canal therapy in patients with pulpal or peri-radicular pathosis. METHODS We searched PubMed, EMBASE, Scopus, and the Cochrane Library as well as the top three endodontic journals for relevant papers. We included randomized controlled trials that included adults. Our main outcome was postoperative pain intensity measured with a validated scale. We assessed the risk of bias using the Cochrane criteria and the quality of the included studies using GRADE. We used a random-effects model for meta-analysis. RESULTS Eight studies involving 810 patients were included. The overall risk of bias was moderate. Seven of eight studies used a visual analog scale to measure pain intensity. Compared with controls, intracanal cryotherapy significantly reduced postoperative pain at 6 (mean difference [MD] -1.37; 95% confidence interval [CI] -0.61 to -2.14; P < 0.05; I2 = 76%; moderate quality evidence) and 24 hours after the procedure (MD -1.43; 95% CI -0.70 to -2.15; P < 0.05; I2 = 89%; moderate quality evidence). There was no significant effect on pain at 48 and 72 hours and 7 days after the procedure. CONCLUSIONS Moderate quality evidence suggests that intracanal cryotherapy, i.e., using cold saline irrigation as a final irrigant, significantly reduces the intensity of pain at 6 and 24 hours after root canal therapy. Future clinical trials assessing the effectiveness of intracanal cryotherapy is advocated.