Comparison of postoperative pain using two instrumentation techniques followed by laser irradiation in nonvital teeth with symptomatic apical periodontitis: A double-blind randomized controlled trial

Aim: Postoperative pain can be caused due to apical extrusion of debris following chemomechanical preparation. This study aimed to compare mechanized reciprocating stainless steel files and continuous rotary instrumentation with laser irradiation for postoperative pain in nonvital teeth with symptomatic apical periodontitis. Methods: Ninety (n = 30) subjects were enrolled after obtaining written consent. In Group 1, continuous rotary instrumentation using Endostar E3 Azure files without laser irradiation, in Group 2, continuous rotary instrumentation using Endostar E3 Azure files with laser irradiation, and in Group 3, mechanized reciprocating instrumentation using K-Flex hand files in K-400 Reciprocating handpiece along with laser irradiation was carried out. Postoperative pain was recorded using Visual Analog Scale at baseline, 24, 48, and 72 h. Subjects requiring rescue medications were recorded. Kruskal–Wallis and Post hoc Tukey's test for intergroup group and pairwise comparison, respectively, and the Chi-square test for comparison of rescue medication were used. Results: The reduction in pain scores was found to be statistically significant (P < 0.05, confidence interval 95%) in all three groups at all-time points. The order of maximum pain reduction was found to be most in Group 2, followed by Group 3 and Group 1. Nine, three, and six subjects required rescue medication in Groups 1, 2, and 3, respectively. Conclusion: Mechanized reciprocating handpiece instrumentation using K-flex files as well as continuous rotary instrumentation using NiTi rotary files along with laser therapy resulted in significantly lesser postoperative pain levels than with continuous rotation alone.