title: Laser therapy in bone repair in rats: analysis of bone optical density.
abstract: OBJECTIVE
  To investigate, by digital radiology, the bone regeneration process in rats submitted to femoral osteotomy and treated with low power laser therapy.
  
  
  METHODS
  Forty-five Wistar rats were subjected to transverse osteotomy of the right femur and divided randomly into three experimental groups (n = 15): animals not treated with laser therapy G (C), animals that received laser therapy with λ: 660nm G (660nm) and animals that received laser therapy with λ: 830nm G (830nm). Animals were sacrificed after 7, 14 and 21 days. The bone calluses were evaluated by digital X-ray at 65 kVp, 7mA and 0.032 s exposures.
  
  
  RESULTS
  The values obtained were submitted to variance analysis (ANOVA) followed by the Tukey-Kramer test. The significance level adopted was 5%. The groups G (C), G (660nm), and G (830nm) at the 7(th) day showed a significant bone development, with p <0.0116; the groups G (C), G (660nm), and G (830nm) at the 14(th) day showed values of p <0.0001; at the 21(st) day,a higher degree of bone repair were observed in group G (830nm), and G (660nm), with p <0.0169.
  
  
  CONCLUSIONS
  Based on the radiographic findings, G (830nm) showed more complete bone regeneration, as shown in the gray shades of the images. Level of Evidence II, Individual Study With Experimental Design.
authors.affiliation: Universidade Camilo Castelo Branco, São José dos Campos, SP, Brasil, Universidade Camilo Castelo Branco, São José dos Campos, SP, Brasil.
authors.forename: Danillo
authors.initials: D
authors.lastname: Barbosa
authors.affiliation: Universidade Camilo Castelo Branco, São José dos Campos, SP, Brasil, Universidade Camilo Castelo Branco, São José dos Campos, SP, Brasil.
authors.forename: Antonio Guillermo Jose Balbin
authors.initials: AG
authors.lastname: Villaverde
authors.affiliation: Universidade do Vale do Paraíba, São José dos Campos, SP, Brasil, Universidade do Vale do Paraíba, São José dos Campos, SP, Brasil.
authors.forename: Emilia Ângela
authors.initials: EÂ
authors.lastname: LoschiavoArisawa
authors.affiliation: Instituto Federal de Educação, Ciência e Tecnologia, Muzambinho, MG, Brasil, Instituto Federal de Educação, Ciência e Tecnologia, Muzambinho, MG, Brasil.
authors.forename: Renato Aparecido
authors.initials: RA
authors.lastname: de Souza
keywords: Fracture healing; Fractures, bone; Osteotomy; Rats, wistar; Technology, radiologic