Photobiomodulation Therapy in the Treatment of Temporomandibular Disorders

Abstract

Temporomandibular disorders (TMD) are a set of characteristic clinical conditions of pain or discomfort of nondental origin, in the masticatory muscles, temporomandibular joint (TMJ) and associated structures. The main symptoms of these disorders are: cracking in the joints, difficulty in opening and closing the mouth, and pain. Therapies for treating TMD involve dietary and behavioral changes, pharmacotherapy, physical therapy, occlusal splint therapy, lasers or open joint surgery. In particular, the use of low-level laser (LLLT) is a non-invasive and non-pharmacological treatment that has shown beneficial results in the treatment of TMD-related pain. It may act through several mechanisms of action, including facilitating the release of endogenous opioids, increasing tissue repair and cellular respiration, increasing vasodilation and pain threshold, and decreasing inflammation. OBJECTIVE: To carry out a bibliographic survey on the efficacy of using LLLT in the treatment of TMD. METHODS: A narrative review was carried out, whose searches dated from November 2021 and in the databases: PubMed, Scielo, Llilacs and BBO. The descriptors "photobiomodulation therapy" and "temporomandibular disorders" and their corresponding ones in English were used. Articles published from 2011 to 2021, in Portuguese, English and Spanish, were included, prioritizing randomized clinical trials and systematic reviews. RESULTS: After reading the titles and abstracts of the 130 articles, 63 were selected for full reading. In the end, 18 were selected. There was positive corroboration among 11 of the authors regarding the effectiveness of low-power laser in improving chronic TMD pain. Its use offers advantages, as the therapeutic regimen is noninvasive, reversible, with fewer adverse effects. Despite this, there is still no consensus on the protocols to be used. Therefore, it is necessary to analyze each case and individualize the treatment in relation to the laser parameters, the number and duration of applications and the characteristics of the light beam. CONCLUSION: The evidence showed that the use of LLLT was effective in reducing symptoms resulting from TMD.