title: Effect of low-level laser therapy and calcitonin on bone repair in castrated rats: a densitometric study.
abstract: OBJECTIVE
  To investigate the healing of bone defects in male rats treated with salmon calcitonin, low-level laser therapy (LLLT), or both.
  
  
  BACKGROUND
  Healing of bone defects still represents a challenge to health professionals in several areas. In this article, the effect of calcitonin in combination with LLLT on bone repair was studied. Densitometry was used as a valuable tool for the measurement of bone regeneration.
  
  
  METHODS
  Sixty male Wistar rats underwent bilateral castration surgery before the creation of a surgical bone defect. The animals were randomly divided into four groups: control, treated with calcitonin (Ca), treated with LLLT (La), and treated with calcitonin and LLLT (CaLa). Groups Ca and CaLa received 2 IU/kg of synthetic salmon calcitonin intramuscularly three times a week. Groups La and CaLa received laser therapy using a gallium-aluminum-arsenide laser (10 mW, 20 J/cm(2), wavelength 830 nm). Control animals were submitted to sham irradiation. The animals were sacrificed 7, 14, and 21 days after surgery, and bone defects were analyzed using densitometry.
  
  
  RESULTS
  The CaLa group had a higher degree of bone regeneration 14 and 21 days after surgery.
  
  
  CONCLUSIONS
  The La and CaLa had significantly higher bone mineral density than the control and Ca groups.
authors.affiliation: Biomedical Vibrational Spectroscopy Laboratory, Universidade do Vale do Paraíba, São José dos Campos, São Paulo, Brazil.
authors.forename: Simone Bustamante
authors.initials: SB
authors.lastname: Nascimento
authors.forename: Claudia Alessandra
authors.initials: CA
authors.lastname: Cardoso
authors.forename: Tatiana Pinto
authors.initials: TP
authors.lastname: Ribeiro
authors.forename: Janete Dias
authors.initials: JD
authors.lastname: Almeida
authors.forename: Regiane
authors.initials: R
authors.lastname: Albertini
authors.forename: Egberto
authors.initials: E
authors.lastname: Munin
authors.forename: Emília Angela Loschiavo
authors.initials: EA
authors.lastname: Arisawa
mesh_terms: D015502:Absorptiometry, Photon; D000704:Analysis of Variance; D000818:Animals; D001861:Bone Regeneration / Q000187:drug effects* / Q000528:radiation effects*; D002116:Calcitonin / Q000494:pharmacology*; D002369:Castration; D005269:Femur / Q000000981:diagnostic imaging / Q000187:drug effects* / Q000528:radiation effects* / Q000601:surgery; D028022:Low-Level Light Therapy / Q000295:instrumentation / Q000379:methods*; D008297:Male; D023421:Models, Animal; D011897:Random Allocation; D051381:Rats; D017208:Rats, Wistar
chemical_list: C028815:salmon calcitonin; D002116:Calcitonin