title: Low level laser effects on pain to palpation and electromyographic activity in TMD patients: a double-blind, randomized, placebo-controlled study.
abstract: The purpose of this study was to evaluate the effect of diode laser (GaAIAs - 780 nm) on pain to palpation and electromyographic (EMG) activity of the masseter and anterior temporalis muscles. The laser was applied on the temporalis and masseter muscles twice a week (four weeks). Forty-eight (48) patients with myofascial pain were randomly assigned between actual and placebo treatments and between the energetic doses of 25 J/cm2 and 60 J/cm2, and were evaluated using VAS before, immediately after the final application, and 30 days after the laser treatment. Surface electromyography was performed with maximum dental clenching before and after laser therapy. The results show there were no significant statistical differences in the EMG activity between the groups before and after laser treatment. With regard to the pain at palpation, although both groups presented a significant difference in the symptoms before and after the treatment, only the active doses showed statistically significant reductions in pain level in all the regions of the palpated muscles. However, there was no significant statistical difference between groups (experimental and placebo). In conclusion, low level laser did not promote any changes in EMG activity. The treatment did, however, lessen the pain symptoms in the experimental groups.
authors.affiliation: Department of Restorative Dentistry, School of Dentistry of Ribeirão Preto, University of São Paulo, Brazil.
authors.forename: Giovana Cherubini
authors.initials: GC
authors.lastname: Venezian
authors.forename: Marco Antônio Moreira Rodrigues
authors.initials: MA
authors.lastname: da Silva
authors.forename: Rafaela Galli
authors.initials: RG
authors.lastname: Mazzetto
authors.forename: Marcelo Oliveira
authors.initials: MO
authors.lastname: Mazzetto
mesh_terms: D000293:Adolescent; D000328:Adult; D004311:Double-Blind Method; D004576:Electromyography; D005157:Facial Pain / Q000503:physiopathology / Q000532:radiotherapy*; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D054023:Lasers, Semiconductor / Q000627:therapeutic use; D028022:Low-Level Light Therapy / Q000379:methods*; D008297:Male; D008406:Masseter Muscle / Q000503:physiopathology / Q000528:radiation effects*; D008875:Middle Aged; D009119:Muscle Contraction / Q000502:physiology; D010147:Pain Measurement; D010173:Palpation; D010919:Placebos; D011879:Radiotherapy Dosage; D012815:Signal Processing, Computer-Assisted; D013703:Temporal Muscle / Q000503:physiopathology / Q000528:radiation effects*; D013705:Temporomandibular Joint Disorders / Q000503:physiopathology / Q000532:radiotherapy*; D055815:Young Adult
chemical_list: D010919:Placebos