To assess the efficacy of PBMT on reducing postoperative pain scores in patients submitted to third molar extractions. A randomized controlled trial (ReBEC:RBR-94BCKZ) was designed according to the SPIRIT and followed the CONSORT. Patients were randomly allocated according to control or PBMT groups. PBMT consisted of the application of GaAlAs laser (808nm;50mW) applied in six points (1.23 min;11 J/cm2) after extraction. Pain scores were assessed using the Visual Analogue Scale (VAS) in millimeters evaluated after 6 (T6), 24 (T24), and 48 (T48) hours. The Wilcoxon Mann?Whitney test was used to check for possible associations between VAS scores and treatment groups. A total of 101 third molar extractions were performed in 44 patients. The mean age was 28 years old(SD±11.54). Comparing control and intervention, PBMT group showed a significant effect on the reduction of postoperative pain at T6(mean VAS=0.9; C.I:0.63?1.16) compared to control (mean VAS=2.5;C.I:2.1?2.88)(p<0.001). The same statistically significant effect on the reduction of postoperative pain was observed at T24 (PBMT mean VAS=0.72;C.I:0.51?0.93; control mean VAS=2.86;C.I:2.40?3.31;p<0.001) and T48 (PBMT mean VAS=0.64;C.I:0.36?0.92; control mean VAS=2.86;C.I:2.37?3.34;p<0.001). PBMT significantly reduce the postoperative pain scores when assessed 6, 24, and 48 hours after third molar extractions.