Effect of Cryotherapy and Occlusal Reduction on Postoperative Endodontic Pain in Mandibular First Molars with Symptomatic Apical Periodontitis: A Prospective, Parallel, Double-Blinded Randomized Controlled Trial.

Abstract

Objectives:  This study aimed to compare the intensity of postoperative pain following the final rinse using cold saline compared with room temperature saline and occlusal reduction.

Materials and methods:  A prospective, parallel, double-blinded randomized controlled trial was conducted on 69 first mandibular molars diagnosed with symptomatic irreversible pulpitis and symptomatic apical periodontitis. Single-visit root canal treatment was performed; access cavity preparations and chemomechanical preparations were carried out using the ProTaper Gold rotary system under copious irrigation using 3% sodium hypochlorite and 17% EDTA. The patients were divided into three groups (n = 23): control group: room temperature saline (25°C) final rinse without occlusal reduction; cryotherapy group: cold saline (2.5-4°C) final rinse without occlusal reduction; and occlusal reduction group: room temperature saline with occlusal reduction. Pain scores were recorded using the visual analog scale preoperatively and postoperatively via telephone at 6, 24, 48, 72 hours, and 7 days intervals. Age data were analyzed using one-way analysis of variance followed by Tukey's post hoc test. Pain score data were analyzed using Kruskal-Wallis' test followed by Dunn's post hoc test for intergroup comparisons and Friedman's test followed by Nemenyi's post hoc test for intragroup comparisons. Correlations were analyzed using Spearman's rank-order correlation coefficient. The significance level was set at p < 0.05 within all tests.

Results:  Cryotherapy reduced postoperative pain compared with the control group with a statistically significant difference at 24 hours only (p = 0.016). At other intervals, no statistically significant difference in pain score was measured between all three groups (p > 0.05). After 7 days, all patients recorded a zero pain score.

Conclusion:  Cryotherapy was as effective as the occlusal reduction in reducing postoperative pain in cases of symptomatic irreversible pulpitis with symptomatic apical periodontitis, significantly more than the control group.