The aim of the study was to compare the effect of Ibuprofen and the application of photobiomodulation therapy protocol on the reduction of postoperative pain in endodontically treated teeth using a randomized clinical trial design. Seventy patients, diagnosed with symptomatic irreversible pulpitis, were selected. Treatment was performed by a single operator; a reciprocal system was used to prepare the canals; they were obturated using the Tagger's hybrid technique and coronally sealed with glass-ionomer cement. After treatment, patients were randomly divided into 2 groups. In the active control group, two Ibuprofen 600 mg tablets were administered within a 12-h interval. In the photobiomodulation therapy group, the irradiation was applied after treatment. The evaluation of postoperative pain was performed by another researcher blinded to the groups at 6, 12, 24, and 72 h intervals after treatment. To measure the outcome, two pain scales were used: numerical rate scale (NRS) and verbal rate scale (VRS). Data were analyzed using the chi-square, Mann-Whitney, and Wilcoxon paired tests. Outcome was superior with photobiomodulation therapy at 6 h (p < 0.001), 12 h (p = 0.005), and 24 h (p < 0.001) intervals compared with Ibuprofen. The results for the 72 h (p = 0.317) interval were similar, both in the VRS and NRS scales. It may be concluded that the use of photobiomodulation therapy was effective in reducing pain within the first 24 h when compared with the administration of Ibuprofen 600 mg.
Keywords: Clinical trial; Endodontics; Ibuprofen; Photobiomodulation therapy; Postoperative pain.