title: Comparison of Red and Infrared Low-level Laser Therapy in the Treatment of Acne Vulgaris.
abstract: OBJECTIVE
  Acne vulgaris is a very prevalent skin disorder and remains a main problem in practice. Recently, phototherapy with various light spectrums for acne has been used. There are some evidences that low-level laser therapy (LLLT) has beneficial effect in the treatment of acne lesions. In this study, two different wavelengths of LLLT (630 and 890 nm) were evaluated in treatment of acne vulgaris.
  
  
  METHODS
  This study was a single-blind randomized clinical trial. Patients with mild to moderate acne vulgaris and age above 18 years and included were treated with red LLLT (630 nm) and infrared LLLT (890 nm) on the right and left sides of the face respectively, twice in a week for 12 sessions, and clinically assessed at baseline and weeks 2, 4, 6, and 8.
  
  
  RESULTS
  Twenty-eight patients were participated in this study. Ten weeks after treatment acne lesion were significantly decreased in the side treated by 630 nm LLLT (27.7±12.7 to 6.3±1.9) (P<0.001), but this decrease was not significant in the site treated by 890 nm LLLT (26.9±12.4 to 22.2±8.5) (P>0.05).
  
  
  CONCLUSIONS
  Red wavelength is safe and effective to be used to treat acne vulgaris by LLLT compared to infrared wavelength.
authors.affiliation: Department of Dermatology, Hazrat-e Rasool University Hospital, Tehran University of Medical Sciences, Tehran, Iran.
authors.forename: Mir Hadi
authors.initials: MH
authors.lastname: Aziz-Jalali
authors.forename: Seyed Mehdi
authors.initials: SM
authors.lastname: Tabaie
authors.forename: Gholamreza Esmaeeli
authors.initials: GE
authors.lastname: Djavid