The authors performed a review of the literature to evaluate the efficacy of
low level laser therapy (
LLLT) for the treatment of
temporomandibular disorders (TMD). Selection criteria included: 1) human subjects, 2) articles written in English, and 3) randomized placebo-controlled trials. Evaluation was performed according to the CONSORT 2010 criteria. A total of 14 articles were included in the review. Studies varied considerably in terms of methodological design, particularly regarding the site of application of the
laser beam, the number of applications performed, their duration, the
laser beam features (wavelength, frequency, output, dosage), and outcome measures. The outcome of the trials was controversial and not particularly related to any features of the
laser beam, to the number of
laser applications, and their duration. Based on the results of this review no definitive conclusions can be drawn on the efficacy of
LLLT for the treatment of TMD. Many methodological differences among the studies, especially regarding the number and duration of
laser applications and characteristics of the
laser beam (wavelength, frequency, output), do not allow for standardized guidelines for effective treatment with
LLLT. The only indication seems to be that
LLLT is probably more effective for the treatment of
TMJ disorders, and less effective for the treatment of masticatory muscle disorders.