Morphological analysis of second-intention wound healing in rats submitted to 16 J/cm 2 lambda 660-nm laser irradiation.
OBJECTIVE
Low-level laser therapy (LLLT) has been extensively applied to improve wound healing due to some biostimulatory properties presented by laser arrays apparently able to accelerate the cicatricial repair of soft tissue injuries. However, many controversial results have been reported in the literature, probably as a result of the wide sort of different protocols of photobiomodulation employed in those experiments. The goal of this study was to investigate the effect of a low-dose protocol of LLT on the intensity of the inflammatory response and the pattern of collagen fibers' deposition during second-intention wound healing in rodents.


METHODS
Standard-sized wounds were carried out in the back of 24 male rats. Half of them underwent LLLT treatment (16 J/cm 2 ) at 660 nm delivered for 7 days. Eight and 14 days after the wounds were performed, the repairing area was removed and stained in HE and Masson's trichrome, and the inflammatory response, epithelization, and collagen fiber depositions were evaluated.


RESULTS
We found that LLLT was able to slightly reduce the intensity of the inflammatory reaction as well as to enhance substantially the epithelization process at both 8 th and 14 th days. In addition, it also appeared to stimulate the deposition of collagen fibers at the final stages of wound healing.


CONCLUSIONS
The LLLT protocol tested in this study resulted in some improvements in second-intention wound healing in rodents.
Gonzaga Ribeiro
Maria Amalia
MA
Laboratory of Morphology and Structural Biology, Science and Technology Institute, University Tiradentes, Aracaju/SE, Brazil.
Cavalcanti de Albuquerque
Ricardo Luiz
RL
Santos Barreto
Andre Luiz
AL
Moreno de Oliveira
Vitor Garcia
VG
Santos
Thalita Barreto
TB
Freitas Dantas
Carolina Delmondes
CD
D000818:Animals; D002921:Cicatrix / Q000378:metabolism* / Q000532:radiotherapy; D004195:Disease Models, Animal; D024022:Fibrillar Collagens / Q000378:metabolism* / Q000528:radiation effects; D008137:Longitudinal Studies; D028022:Low-Level Light Therapy / Q000295:instrumentation / Q000379:methods*; D008297:Male; D051381:Rats; D016896:Treatment Outcome; D014945:Wound Healing / Q000528:radiation effects*
D024022:Fibrillar Collagens