title: Effect of low-level laser therapy on pain levels in patients with temporomandibular disorders: a systematic review.
abstract: Temporomandibular disorders (TMD) are characterized by the presence of temporomandibular joint (TMJ) and/or masticatory muscle pain and dysfunction. Low-level laser is presented as an adjuvant therapeutic modality for the treatment of TMD, especially when the presence of inflammatory pain is suspected.
  
  
  OBJECTIVE
  To systematically review studies that investigated the effect of low level laser therapy (LLLT) on the pain levels in individuals with TMD.
  
  
  METHODS
  The databases Scopus, embase, ebsco and PubMed were reviewed from January/2003 to October/2010 with the following keywords: laser therapy, low-level laser therapy, temporomandibular joint disorders, temporomandibular joint dysfunction syndrome, temporomandibular joint, temporomandibular, facial pain and arthralgia, with the inclusion criteria for intervention studies in humans. exclusion criteria adopted were intervention studies in animals, studies that were not written in english, Spanish or Portuguese, theses, monographs, and abstracts presented in scientific events.
  
  
  RESULTS
  After a careful review, 14 studies fit the criteria for inclusion, of which, 12 used a placebo group. As for the protocol for laser application, the energy density used ranged from 0.9 to 105 J/cm², while the power density ranged from 9.8 to 500 mW. The number of sessions varied from 1 to 20 and the frequency of applications ranged from daily for 10 days to 1 time per week for 4 weeks. A reduction in pain levels was reported in 13 studies, with 9 of these occurring only in the experimental group, and 4 studies reporting pain relief for both the experimental group and for the placebo.
  
  
  CONCLUSIONS
  Most papers showed that LLLT seemed to be effective in reducing pain from TMD. However, the heterogeneity of the standardization regarding the parameters of laser calls for caution in interpretation of these results. Thus, it is necessary to conduct further research in order to obtain a consensus regarding the best application protocol for pain relief in patients with TMD.
authors: Federal University of Sergipe, Aracaju, SE, Brazil. milademoraes@hotmail.com
authors: Mila Leite de Moraes
authors: ML
authors: Maia
authors: Leonardo Rigoldi
authors: LR
authors: Bonjardim
authors: Jullyana de Souza Siqueira
authors: Jde S
authors: Quintans
authors: Maria Amália Gonzaga
authors: MA
authors: Ribeiro
authors: Luiz Guilherme Martins
authors: LG
authors: Maia
authors: Paulo César Rodrigues
authors: PC
authors: Conti
mesh_terms: D002985:Clinical Protocols; D005157:Facial Pain / Q000532:radiotherapy*; D006801:Humans; D028022:Low-Level Light Therapy; D010147:Pain Measurement; D011829:Radiation Dosage; D013705:Temporomandibular Joint Disorders / Q000532:radiotherapy*; D016896:Treatment Outcome