Effectiveness of low-level gallium aluminium arsenide laser therapy for temporomandibular disorder with myofascial pain

Abstract

Purpose: Temporomandibular disorder (TMD) causes masticatory muscle pain and mouth opening limitations and affects patients’ ability to eat, practice oral health and perform other activities of daily living. Although the benefits of low-energy lasers in treating TMD have been reported, the results vary greatly depending on the equipment used and the energy output. This study systematically evaluated the efficacy of a low-level gallium aluminium arsenide (GaAlAs) laser treatment for TMD with myofascial pain and maxillary pain. Methods: We searched the PubMed, EMBASE, Cochrane Library, Web of Science, and ClinicalTrials.gov databases for randomized controlled trials (RCTs) published since database inception to April 5, 2020, that compared low-level laser treatment to sham/placebo treatment or no intervention in patients suffering from TMD with myofascial pain. Three reviewers independently screened the literature, extracted data, and assessed the quality of the included studies according to the risk-of-bias tool recommended by the Cochrane Handbook V.5.1.0 (Cochrane Collaboration, London, UK). Then, a meta-analysis was performed using RevMan 5.3 and Stata 15.1 software. Results: The data from 8 randomized controlled trials including 181 patients were analyzed. The severity of myofascial TMD pain (measured on a visual analogue scale, VAS) at the end of treatment was significantly different between the control laser therapy and the low-level GaAlAs laser therapy (weighted mean difference [WMD] = −0.76, 95% confidence interval [CI] −1.51 to 0.01, P = .046); at 3 to 4 weeks after treatment, there was no significant difference (WMD = 1.24, 95% CI −0.04 to 2.51, P = .057). In addition, there was no significant improvement in maximum mouth opening (MMO) at the end of treatment (WMD = −0.03, 95% CI −4.13 to 4.06, P = .987) or at 3 to 4 weeks after treatment (WMD = 1.22, 95% CI −2.94 to 5.39, P = .565). Conclusions: The results of this study suggest that there is insufficient evidence to indicate an efficacy of low-level GaAlAs laser therapy in improving TMD pain and maximal oral opening. These results suggest that clinicians should make appropriate recommendations to inform patient decision-making.

Comparison of low‐level laser therapy and standard treatment for temporomandibular disorders: An assessment of therapeutic and placebo effects

“…[4][5][6][7] Physical therapy is a noninvasive and reversible treatment option LLLT's effectiveness for TMD treatment has been debated in previous studies. 6,9,13,15,16,26,27 These studies were limited by several drawbacks, including a high risk of bias, uncertainty regarding the randomization and blinding methods, small sample sizes, and unclear criteria for patient selection and treatment protocols. These limitations highlight the importance of conducting well-designed studies with rigorous methodology to establish the true effectiveness of LLLT for temporomandibular disorder.…”

“…In many previous studies, the criteria for TMD diagnosis were unclear, making it difficult to compare people participating in different studies. 6,13,16 To address this, the DC/TMD guidelines for diagnosing TMD were used in the present study for research and clinical purposes. 2 Laser treatment was performed by a trained operator outside of the study to minimise clinician bias.…”

“…For example, in a more detailed review of previous studies, it was found that the time of onset of pain (acute or chronic pain) was not specified, while in this study, almost all patients (95.2%) had chronic pain lasting over 6 months. 6,13,35 According to the Biopsychosocial model of pain, the psychosocial aspect of pain has a greater contribution to the continuation of pain in chronic pain, while in acute pain, the biological component, which includes the inflammatory response and chemical mediators like inflammatory cytokines, has a greater contribution to causing pain. 29 The exact mechanisms of how LLLT works for pain manage- and creating a collateral blood network in the damaged area.…”

“…12 Despite extensive research on the use of low-power lasers for TMD treatment, the extent of their effectiveness remains uncertain. 6,[13][14][15][16][17] Low-power lasers emit electromagnetic radiation in the spectrum of red or infrared light waves and are used to treat various pathological conditions such as wound healing problems, pain and inflammation. [18][19][20][21] Review articles and various studies on the therapeutic effect of low-power lasers in reducing pain and improving the conditions of patients with chronic musculoskeletal disorders such as osteoarthritis in the knees and spine have reported positive results.…”

“…Review and meta-analysis studies that have clinically investigated the effect of LLLT on TMD suggest that the lack of a specific treatment protocol, failure to use standard diagnostic criteria, insufficient sample size and the possibility of bias are among the reasons for the differing results. 6,[13][14][15][16][17]26,27 Due to its deceptive appearance, laser therapy is a tool with complex technology and extensive commercial advertising. It has a placebo effect on patients, like any other treatment.…”