ABSTRACT
AIM: Conducting a systematic review of randomized clinical trials focusing on the efficacy of LLLT on pain control in patients with TMD, diagnosed by the Research Diagnostic Criteria for Temporomandibular Disorders (RDC/TMD). MATERIAL AND METHODS: Search was performed at PubMed/MEDLINE database with the terms: (1) "Laser AND temporomandibular disorders"; (2) "Laser AND temporomandibular disorders AND RDC/TMD"; (3) "Low-level laser therapy AND temporomandibular disorders"; (4) "Low-level laser therapy AND temporomandibular disorders AND RDC/TMD"; (5) "Low-level laser therapy AND temporomandibular joint dysfuntion syndrome"; (6) "Low-level laser therapy AND temporomandibular joint dysfuntion syndrome AND RDC/TMD"; (7) "Laser AND temporomandibular joint dysfuntion syndrome" (8) "Laser AND RDC/TMD"; (9) "Low-level laser therapy AND RDC/TMD". Inclusion criteria: articles need to be randomized clinical trial performed in humans; evaluate the effect of LLLT in the treatment of TMD diagnosed by the use of RDC/TMD; published in English or Portuguese in the last 10 years. Protocol studies and pilot studies were excluded. RESULTS: Ten studies were included. The type of laser used was Gallium Aluminum Arsenide (GaAlAs) diode, with exception of 1 paper, which used super pulsed Gallium Arsenide laser. Eight studies reported decreased in pain levels, in two articles there was no statistically significant difference between test and placebo groups. CONCLUSION: In most studies, LLLT was effective in pain remission, but there is no standardization in parameters like wavelength, output power and frequency. Studies with more complex experimental designs, standardized diagnostic criteria for TMD and defined protocols for the use of LLLT are needed to determine its efficacy in the treatment of TMD.