Low level laser therapy for the treatment of temporomandibular disorders: a systematic review of the literature.
ABSTRACT 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.
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ABSTRACT: Evidence strongly supports that low-level laser therapy (LLLT) is an effective physical modality for the treatment of pain associated with myofascial trigger points (MTrP). However, the effect of laser fluence (energy intensity in J/cm(2)) on biochemical regulation related to pain is unclear. To better understand the biochemical mechanisms modulated by high- and low-fluence LLLT at myofascial trigger spots (MTrSs; similar to human MTrPs) in skeletal muscles of rabbits, the levels of β-endorphin (β-ep), substance P (SP), tumor necrosis factor-α (TNF-α), and cyclooxygenase-2 (COX-2) were investigated in this study. New Zealand rabbits (2.5-3.0 kg in weight) were used in this study. High-fluence LLLT (27 J/cm(2)), low-fluence LLLT (4.5 J/cm(2)), or sham operations were applied on MTrSs of biceps femoris of rabbits for five sessions (one session per day). Effects of LLLT at two different fluences on biceps femoris, dorsal root ganglion (DRG), and serum were determined by β-ep, SP, TNF-α, and COX-2 immunoassays. LLLT irradiation with fluences of 4.5 and 27 J/cm(2) at MTrSs can significantly reduce SP level in DRG. LLLT with lower fluence of 4.5 J/cm(2) exerted lower levels of TNF-α and COX-2 expression in laser-treated muscle, but LLLT with higher fluence of 27 J/cm(2) elevated the levels of β-ep in serum, DRG, and muscle. This study demonstrated fluence-dependent biochemical effects of LLLT in an animal model on management of myofascial pain. The findings can contribute to the development of dosage guideline for LLLT for treating MTrP-induced pain.Lasers in Medical Science 09/2014; 30(1). DOI:10.1007/s10103-014-1654-9 · 2.42 Impact Factor
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ABSTRACT: According to the International Association for the Study of Pain (IASP), the term temporomandibular disorder (TMD) regards a subgroup of orofacial pain, the symptoms of which include pain or discomfort in the temporomandibular joint, ears, masticatory muscles and neck on one or both sides, as well as joint sounds, limited mandibular movements or mandibular deviation and difficulties chewing. Phototherapy, such as low-level laser therapy (LLLT) and light-emitting diode (LED) therapy, is one of the resources used to treatment muscle pain. Thus, there is a need to investigate therapeutic resources that combine different wavelengths as well as different light sources (LLLT and LED) in the same apparatus.The aim of the proposed study is to evaluate the effects of four different doses of phototherapy on pain, activity of the masticatory muscles (masseter and bilateral anterior temporal) and joint mobility in individuals with temporomandibular disorder (TMD). A further aim is to determine the cumulative effect 24 and 48 hours after a single session. A placebo-controlled, double-blind, randomized, clinical trial will be carried out involving 72 women between 18 and 40 years of age with a diagnosis of myogenous TMD. The participants will then be randomly allocated to four groups totaling 18 individuals per group. Three groups will be submitted to a single session of phototherapy with different light sources, and one group will receive placebo therapy: Group A (2.62 Joules); Group B (5.24 Joules); Group C (786 Joules); and Group D (0 Joules). The following assessment tools will be administered on four separate occasions (baseline and immediately after, 24 h after and 48 h after phototherapy). Pain intensity will be assessed using the visual analog scale for pain, while pain thresholds will be determined using algometer, and electromyographic (EMG) analysis on the masseter and anterior temporal muscles. The study will contribute to the practice of the evidence-based use of phototherapy in individuals with a myogenous TMD. Data will be published after the study is completed.Trial registration: This study is registered with the Brazilian Registry of Clinical Trials, NCT02018770, date of registration: 7 December 2013.Trials 12/2014; 15(1):491. DOI:10.1186/1745-6215-15-491 · 2.12 Impact Factor
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ABSTRACT: Objective To investigate the clinical effects of laser acupuncture therapy for temporomandibular disorders (TMD) after ineffective previous treatments. Methods A retrospective observational study was conducted in 29 treatment-resistant TMD patients (25 women, 4 men; age range, 17–67 years). Subjects were treated 3 times per week for 4 weeks with the Handylaser Trion (GaAlAs laser diode, 810 nm, 150 mW, pulsed waves), which delivered 0.375 J of energy (5 s) to ST7, ST6, and LI4 and 3 J (40 s) to each Ashi point, 7.5–26.25 J/cm2 in total. The visual analog scale (VAS) and maximal mouth opening (MMO) were evaluated before and after treatment. Results VAS analysis showed that the patients were free of pain at rest (endpoint) after 5.90±6.08 sessions of laser acupuncture for acute TMD and after 16.21±17.98 sessions for chronic TMD. The VAS score on palpation of the temporomandibular joint reduced to 0.30±0.67 for patients with acute TMD (p = 0.005) and to 0.47±0.84 for those with chronic TMD (p<0.001). The MMO significantly increased in patients with acute TMD (7.80±5.43 mm, p = 0.008) and in patients with chronic TMD (15.58±7.87 mm, p<0.001). Conclusions Our study shows that laser acupuncture therapy improves the symptoms of treatment-resistant TMD. Further studies with a more appropriate design, involving long-term follow-up examinations in a larger patient sample, are needed to evaluate its efficacy.PLoS ONE 10/2014; 9(10):e110528. DOI:10.1371/journal.pone.0110528 · 3.53 Impact Factor