title: Infrared laser light further improves bone healing when associated with bone morphogenic proteins: an in vivo study in a rodent model.
abstract: OBJECTIVE
  This study assessed histologically the effect of laser photobiomodulation (LPBM) on the repair of surgical defects created in the femurs of Wistar rats treated or not treated with bone morphogenic proteins (BMPs) and organic bovine bone graft.
  
  
  BACKGROUND
  This paper is part of an ongoing series of works in which biomaterials are used in association with LPBM. Several previous reports by our group have shown that the use of laser photobiomodulation improves the treatment of bone defects.
  
  
  METHODS
  Forty-eight adult male Wistar rats were divided into four randomized groups: group I (control, n = 12); group II (LPBM, n = 12); group III (BMPs + organic bovine bone graft, n = 12); and group IV (BMPs + organic bovine bone graft + LPBM, n = 12). The irradiated groups received seven irradiations every 48 h, beginning immediately after the surgical procedure. The laser therapy (lambda = 830 nm, 40 mW CW, varphi = 0.6 mm) consisted of 16 J/cm(2) per session divided equally over four points (4 J/cm(2) each) around the defect. The subjects were sacrificed after 15, 21, and 30 d, and the specimens were routinely embedded in wax, stained with hematoxylin and eosin and sirius red, and analyzed under light microscopy.
  
  
  RESULTS
  The results showed histological evidence of increased deposition of collagen fibers (at 15 and 21 d), as well as an increased amount of well-organized bone trabeculae at the end of the experimental period (30 d) in the irradiated animals versus the non-irradiated controls.
  
  
  CONCLUSIONS
  The use of LPBM with BMPs and organic bovine bone grafts increases the positive biomodulating effects of laser light.
authors.affiliation: School of Dentistry, Federal University of Pernambuco, Recife, PE, Salvador.
authors.forename: Marleny E Martinez
authors.initials: ME
authors.lastname: Gerbi
authors.forename: Aparecida M C
authors.initials: AM
authors.lastname: Marques
authors.forename: Luciana Maria Pedreira
authors.initials: LM
authors.lastname: Ramalho
authors.forename: Elizabeth Arruda Carneiro
authors.initials: EA
authors.lastname: Ponzi
authors.forename: Carolina Montagn
authors.initials: CM
authors.lastname: Carvalho
authors.forename: Rafael De Carneiro
authors.initials: Rde C
authors.lastname: Santos
authors.forename: Priscila Chagas
authors.initials: PC
authors.lastname: Oliveira
authors.forename: Manuela
authors.initials: M
authors.lastname: Nóia
authors.forename: Antonio Luiz B
authors.initials: AL
authors.lastname: Pinheiro
mesh_terms: D000818:Animals; D001672:Biocompatible Materials / Q000008:administration & dosage*; D019485:Bone Morphogenetic Proteins / Q000008:administration & dosage*; D001861:Bone Regeneration / Q000187:drug effects* / Q000528:radiation effects*; D005269:Femur / Q000187:drug effects / Q000503:physiopathology / Q000528:radiation effects; D007259:Infrared Rays / Q000627:therapeutic use*; D028022:Low-Level Light Therapy / Q000379:methods*; D008297:Male; D051381:Rats; D017208:Rats, Wistar
chemical_list: D001672:Biocompatible Materials; D019485:Bone Morphogenetic Proteins