title: Effects of Low-level Laser in the Treatment of Myofascial Pain Dysfunction Syndrome.
abstract: OBJECTIVE
  Muscular pain in the facial region is the most common cause of facial pains. Myofascial pain dysfunction syndrome (MPDS) is one of the most important facial muscle disorders comprising of signs and symptoms including pain during function, tenderness in the muscles of mastication and restricted jaw movement. Due to the lack of an accepted therapeutic approach, the purpose of this paper was to find an effective treatment to decrease the pain of such patients. Considering the analgesic and anti-inflammatory action of laser therapy, the effects of low level laser (Ga-Al-As) in the treatment of MPDS patients referred to Tehran University of Medical Sciences Faculty of Dentistry, were investigated in the present study.
  
  
  METHODS
  This study was a quasi-experimental research. Twenty-two MPDS patients were selected from those referred to Department of Oral Medicine, Tehran University of Medical Sciences Faculty of Dentistry. Clinical examination was performed at six stages in the following order: prior to the treatment, at 2 and 4 weeks after treatment, and monthly thereafter for a 3-months follow-up. All patients underwent low-level laser therapy for 4 weeks (12 sessions). Variables such as pain severity, pain of cheek region, pain frequency, tenderness of masticatory muscles, click, and mouth opening were evaluated at each stage. Numerical variables were investigated using Analysis of Variance test for repeated measures whereas ranking variables were studied by non-parametric Kruskal-Wallis test.
  
  
  RESULTS
  At the end of treatment period, pain severity, pain of cheek region, pain frequency, tenderness of masseter, temporalis, medial pterygoid, and lateral pterygoid muscles showed significant improvement as compared with the commencement of any treatment which continued during the 3-months post-treatment (p<0.05).
  
  
  CONCLUSIONS
  It was shown that low-level laser (Ga-Al-As) therapy had the efficacy to alleviate pain and decrease the tenderness of masticatory muscles among MPDS patients through a continuous and regular therapeutic program.
authors.affiliation: Assistant Professor, Department of Oral Medicine, Faculty of Dentistry, Ahwaz Jondishapoor University of Medical Sciences, Iran.
authors.forename: Arash
authors.initials: A
authors.lastname: Azizi
authors.forename: Mahnaz
authors.initials: M
authors.lastname: Sahebjamee
authors.forename: Shirin
authors.initials: S
authors.lastname: Lawaf
authors.forename: Fereydoon
authors.initials: F
authors.lastname: Jamalee
authors.forename: Nader
authors.initials: N
authors.lastname: Maroofi
keywords: Low-level laser therapy; muscle tenderness; myofascial pain dysfunction syndrome; pain