title: Analgesic action of laser therapy (LLLT) in an animal model.
abstract: OBJECTIVE
  To evaluate the analgesic effect of laser therapy on healthy tissue of mice.
  
  
  METHODS
  Forty-five animals were divided in three groups of 15: A--infrared laser irradiation (830 nm, Kondortech, São Carlos, SP, Brazil); B--red laser irradiation (660 nm, Kondortech, São Carlos, SP, Brazil); C-- ham irradiation with laser unit off. After laser application, the mice remained immobilized for the injection of 30 microl of 2% formalin in the plantar pad of the irradiated hind paw. The time that the mouse kept the hind paw lifted was measured at 5 min intervals for 30 minutes.
  
  
  RESULTS
  Results showed statistically significant differences comparing the control group with the infrared laser group at 5, 20, 25 and 30 accumulated minutes, and with the red laser group at all time points. The analysis of partial times, at each 5 minutes, showed statistically significant differences between the control and the laser groups up to 20 minutes.
  
  
  CONCLUSIONS
  Laser therapy had an analgesic effect and red laser had the best results.
authors.affiliation: Laser Technology, Universidade Federal da Paraíba and Universidade Federal da Bahia, Universidade do Porto, Portugal.
authors.forename: Daniel Humberto
authors.initials: DH
authors.lastname: Pozza
authors.forename: Patrícia Wehmeyer
authors.initials: PW
authors.lastname: Fregapani
authors.forename: João Batista Blessmann
authors.initials: JB
authors.lastname: Weber
authors.forename: Marília Gerhardt
authors.initials: MG
authors.lastname: de Oliveira
authors.forename: Marcos André Matos
authors.initials: MA
authors.lastname: de Oliveira
authors.forename: Nelson
authors.initials: N
authors.lastname: Ribeiro Neto
authors.forename: João Batista
authors.initials: JB
authors.lastname: de Macedo Sobrinho
mesh_terms: D000698:Analgesia / Q000379:methods*; D000818:Animals; D028022:Low-Level Light Therapy; D008297:Male; D051379:Mice; D023421:Models, Animal