Low Intensity Laser Therapy in Temporomandibular Disorder: a Phase II Double-Blind Study

Abstract

The purpose of this study was to evaluate the analgesic effect of Low Intensity Laser Therapy (LILT) and its influence on masticatory efficiency in patients with temporomandibular dysfunction (TMD). This study was performed using a random, placebo-controlled, and double-blind research design. Fourteen patients were selected and divided into two groups (active and placebo). Infrared laser (780 nm, 70 mw, 60s, 105J/cm2) was applied precisely and continuously into five points of the temporomandibular joint (TMJ) area: lateral point (LP), superior point (SP), anterior point (AP), posterior point (PP), and posterior-inferior point (PIP) of the condylar position. This was performed twice per week, for a total of eight sessions. To ensure a double-blind study, two identical probes supplied by the manufacturer were used: one for the active laser and one for the inactive placebo laser. They were marked with different letters (A and B) by a clinician who did not perform the applications. A Visual Analogue Scale (VAS) and a colorimetric capsule method were employed. Data were obtained three times: before treatment (Ev1), shortly after the eighth session (Ev2), and 30 days after the first application (Ev3). Statistical tests revealed significant differences at one percent (1%) likelihood, which implies that superiority of the active group offered considerable TMJ pain improvement. Both groups presented similar masticatory behavior, and no statistical differences were found. With regard to the evaluation session, Ev2 presented the lowest symptoms and highest masticatory efficiency throughout therapy. Therefore, low intensity laser application is effective in reducing TMD symptoms, and has influence over masticatory efficiency [Ev2 (0.2423) and Ev3 (0.2043), observed in the interaction Evaluations x Probes for effective dosage].

A Meta-analysis of Clinical Effects of Low-level Laser Therapy on Temporomandibular Joint Pain

“…As a result of our search for research articles, 7 articles discussing clinical findings with a PEDro score of between 9 and 11 were selected to examine the pain relief effect of LLLT when treating TMJ pain15,16,17,18,19,20,21 ) . All of the treatment parameters and PEDro scores are shown in Table 1…”

“…Therefore, the results are based on the treatment outcomes of 223 subjects in six articles15,16,17, 19,20,21 ) . Four of the articles showed a positive effect on pain relief after LLLT was employed15, 17, 19, 20 ) . But no statistically significant differences (p > 0.05) existed in the results of the studies of Emshoff et al16 ) and Venancio et al21 ) .…”

Efficacy of low-level laser therapy in temporomandibular disorders: A systematic review

“…Carrasco et al . [3] divided 14 patients into two groups (active and placebo) and concluded that low-intensity laser application is effective in reducing TMD symptoms, and also has influence over masticatory efficiency. Shirani et al .…”

Effect of low-level laser therapy on pain levels in patients with temporomandibular disorders: a systematic review

“…Currently, it is disturbing to see the number of patients with TMD treated with non-evidence-based therapies 6 , often without competent professional assistance 37 . As an alternative therapy, LLLT with its analgesic, anti-inflammatory, anti-edematous, and biostimulatory effects has proven to be effective in reducing pain and muscle tension in patients with TMD 7,9,16,21,23,26,35,38 . …”

“…26 (2007); and Carrasco, et al. 7 (2008), who used panoramic radiography, should be analyzed with caution because there is not always a direct association between the findings of such examinations and the presence of signs and symptoms of TMD 1,33 . …”