Effects of a single near-infrared laser treatment on cutaneous wound healing: Biometrical and histological study in rats

Abstract

Background Low intensity laser therapy has been recommended to support the cutaneous repair; however, so far studies do not have evaluated the tissue response following a single laser treatment. This study investigated the effect of a single laser irradiation on the healing of full-thickness skin lesions in rats. Methods Forty-eight male rats were randomly divided into three groups. One surgical lesion was created on the back of rats using a punch of 8 mm in diameter. One group was not submitted to any treatment after surgery and it was used as control. Two energy doses from an 830-nm near-infrared diode laser were used immediately post-wounding: 1.3 J cm −2 and 3 J cm −2. The laser intensity 53 mW cm −2 was kept for both groups. Biometrical and histological analyses were accomplished at days 3, 7 and 14 post-wounding. Results Irradiated lesions presented a more advanced healing process than control group. The dose of 1.3 J cm −2 leaded to better results. Lesions of the group irradiated with 1.3 J cm −2 presented faster lesion contraction showing quicker re-epithelization and reformed connective tissue with more organized collagen fibers. Conclusions Low-intensity laser therapy may accelerate cutaneous wound healing in a rat model even if a single laser treatment is performed. This finding might broaden current treatment regimens.