Effects of 780-nm low-level laser therapy with a pulsed gallium aluminum arsenide laser on the healing of a surgically induced open skin wound of rat.

OBJECTIVE The aim of the present investigation is to evaluate the effects of a 780-nm low-level laser on open skin wound healing. BACKGROUND DATA Optimal parameters of low-level laser therapy (LLLT) for wound healing are discussed. METHODS One full-thickness skin wound was surgically induced in the dorsum skin of 30 rats. The rats were divided into two groups. Rats in the experimental group were daily treated with a gallium aluminum arsenide (GaAlAs) laser (2 J/cm(2), lambda = 780 nm, pulse frequency of 2336 Hz). Rats in the sham-exposed group received LLLT with switched off equipment. After 4, 7, and 15 days, wounds were checked by histological and biomechanical methods. Data were analyzed by the Mann-Whitney U-test. RESULTS Fibroblasts, endothelium of blood vessels, blood vessel sections, and maximum stress were significantly increased, whereas macrophages were significantly decreased, compared with those of the sham-exposed group. CONCLUSION Pulsed LLLT with a 780-nm GaAlAs laser significantly accelerates the process of healing of surgically induced, full-thickness skin wounds in rat.