Low-Level Laser Therapy is More Effective Than Pulse Ultrasound Treatment onWound Healing: Comperative Experimental Study

Abstract

Objective: To investigate and compare the effects of pulse ultrasound (US) and low-level laser therapy (LLLT) on wound healing. Material and Methods: Thirty-two rats were included in the study and two full-thickness skin wounds were made on dorsum area of the rats bilaterally, with a 17 mm hole-punch. The animals were divided into two groups. Pulsed US (with a power of 0.1 W/cm2, a frequency of 1 MHz, 5 minutes daily) was applied to to the right sided wounds of Group A (n= 16) and Ga-As laser (830 nm wavelength, 0.5 J/ cm2 dosage of 1 MHz frequency for 1 minute duration) was applied to right sided wounds of Group B (n= 16). Left sided wound were considered as controls and same procedures were applied without any current (sham). Biochemical and histopathological evaluations were performed in each group on 7th and 15th days. Results: Inflammatory cells tended to decrease in both treatment groups on the 7th day, however, this finding did not reach a statistical significance (p> 0.05). Fibroblasts and collagen were found to be significantly increased in the laser group when compared to the other group on the 7th day (p< 0.05). Angiogenesis was found to be significantly increased only in the laser group when compared to the other group on the 15th day (p< 0.05). There were no significant differences in tissue nitric oxide values between the groups although the values in the laser group tended to be higher on the 15th day (p=0.058) Conclusion: In this comparative study, LLLT was found to significantly accelerate mainly proliferative phase while pulse US had no effect on wound healing. Our results support the consideration that LLLT may constitute a beneficial treatment modality for wound healing.