Infrared laser light further improves bone healing when associated with bone morphogenetic proteins and guided bone regeneration: an in vivo study in a rodent model.
OBJECTIVE
This study assessed histologically the effect of laser photobiomodulation on the repair of surgical defects created in the femurs of Wistar rats treated or not treated with bone morphogenetic proteins (BMPs) and organic bovine bone graft.


BACKGROUND
This paper is part of an ongoing series of works in which biomaterials and/or guided bone regeneration (GBR) are used in association with laser photobiomodulation. Several previous reports from 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 1 (controls, n = 12); group 2 (laser photobiomodulation, n = 12); group 3 (BMPs + organic bovine bone graft + GBR, n = 12); and group 4 (BMPs + organic bovine bone graft + GBR + laser photobiomodulation, n = 12). The irradiated groups received seven irradiations every 48 h, the first immediately after the surgical procedure. Laser photobiomodulation (830 nm, 40 mW, CW, phi approximately 0.6 mm) consisted of a total of 16 J/cm2 per session at four points (4 J/cm2 each) equally spaced around the periphery of the defect. The animals were sacrificed after 15, 21, and 30 d, and the specimens were routinely embedded in wax and stained with hematoxylin and eosin and Sirius red stains 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 trabeculi at the end of the experimental period (30 d) in irradiated animals compared to non-irradiated controls.


CONCLUSIONS
We concluded that the use of laser photobiomodulation in association with BMPs, organic bovine bone grafts, and GBR increases the positive biomodulating effects of laser energy.
Pinheiro
Antonio Luiz B
AL
Laser Center, School of Dentistry, Department of Propedeutica and Clínica Integrada, Universidade Federal da Bahia, Salvador, Brazil. albp@ufba.br
Martinez Gerbi
Marleny E
ME
Carneiro Ponzi
Elizabeth Arruda
EA
Pedreira Ramalho
Luciana Maria
LM
Marques
Aparecida M C
AM
Carvalho
Carolina Montagn
CM
Santos
Rafael de Carneiro
Rde C
Oliveira
Priscila Chagas
PC
Nóia
Manuela
M
D000818:Animals; D001672:Biocompatible Materials / Q000627:therapeutic use; D019485:Bone Morphogenetic Proteins / Q000627:therapeutic use*; D001861:Bone Regeneration / Q000187:drug effects / Q000528:radiation effects*; D005260:Female; D005269:Femur / Q000293:injuries / Q000503:physiopathology* / Q000528:radiation effects*; D048091:Guided Tissue Regeneration / Q000379:methods*; D053685:Laser Therapy; D008297:Male; D051381:Rats; D017208:Rats, Wistar
D001672:Biocompatible Materials; D019485:Bone Morphogenetic Proteins