Efficacy of low-level laser therapy in the treatment of temporomandibular disorder

Aims: To evaluate the effectiveness of low-level laser therapy (LLLT) in patients presenting with temporomandibular disorder (TMD) in a random and placebo-controlled research design. Methods: The sample consisted of 40 patients, divided into an experimental group (G1) and a placebo group (G2). The treatment was done with an infrared laser (830nm, 500mW, 20s, 4J/point) at the painful points, once a week for four consecutive weeks. The patients were evaluated before and after the treatment through a Visual Analogue Scale (VAS) and the Craniomandibular Index (CMI). Results: The baseline and post-therapy values of VAS and CMI were compared by the paired T-test, separately for the placebo and laser groups. A significant difference was observed between initial and final values (p < 0.05) in both groups. Baseline and post-therapy values of pain and CMI were compared in the therapy groups by the two-sample T-test, yet no significant differences were observed regarding VAS and CMI (p > 0.05). Conclusion: After either placebo or laser therapy, pain and temporomandibular symptoms were significantly lower, although there was no significant difference between groups. The low-level laser therapy was not effective in the treatment of TMD, when compared to the placebo.