The Effect of Low-Level Laser Therapy on the Healing of Open Wounds in Dogs.

Abstract

To evaluate the effects of low-level laser therapy (LLLT) on acute, full-thickness wound healing in dogs. Randomized block (dog); historical control. Adult male Beagles (n = 10). Two 2 × 2 cm(2) wounds were surgically created bilaterally on the trunk of each dog. Each side was randomized to receive LLLT (laser, LAS) or standard-of-care management (control, CON), 3 times weekly for 32 days. The LLLT consisted of a dual diode laser (7.5 mW/diode) at 635 nm and total energy density of 1.125 J/cm(2). Wound planimetry was performed on the caudal wounds, from which percent contraction and percent epithelialization were calculated. Histologic features were evaluated at 7 time points from cranial wound biopsies. Experimental data were also compared to wounds from a historical female control cohort (historical control, HCON). There was no difference between LAS and CON wounds for all parameters, including histology. The HCON wounds had significantly greater contraction and epithelialization compared to LAS and CON wounds. The LAS and CON wounds had significantly less inflammation than HCON wounds early in wound healing, but inflammation was significantly greater in LAS and CON wounds by day 21. Fibroblast infiltration and collagen deposition were significantly less in LAS and CON wounds than HCON wounds. There are no apparent beneficial effects of LLLT on the healing of acute wounds in healthy dogs using this LLLT protocol. Gender may influence wound healing in intact dogs.