The effect of indocyanine green-mediated photodynamic therapy in healing of experimentally induced oral mucosal traumatic ulcer in rat

Abstract

Photodynamic therapy (PDT) is a promising approach for the healing of ulcerative lesions. This study aimed to investigate the effect of PDT using indocyanine green (ICG) in the healing of the experimentally induced oral mucosal traumatic ulcer in rat. Sixty adult male Sprague-Dawley rats were recruited in this experimental study. The ulceration was surgically made in the left cheek mucosa, and the rats were randomly assigned into four equal groups (n = 15). Oral ulcers in groups 1 and 2 were treated with the sterile saline solution (0.9%) and ICG (1 mg/ml). In group 3, laser irradiation was applied using the 810 nm diode laser in the continuous-wave mode for 30 s (light dose: 55 J/cm², power: 300 mW, spot size: 4.5 mm). Following the topical application of ICG (1 mg/ml) in group 4, laser irradiation was performed in the same way as the previous group. After 24 h, treatments were repeated once more in all groups. The healing process was histopathologically assessed at the 3rd, 7th, and 14th days after ulceration. Wound healing was significantly accelerated in the ICG-mediated PDT group in comparison to the control group at all sampling time points (p < 0.005). However, the other groups displayed a similar healing rate (p > 0.05). Data suggest that ICG-mediated PDT has the potential to accelerate wound healing and prevent clinical infection in oral mucosal traumatic ulcers. However, further studies are required to confirm whether our results can be generalized to other wounds.

Keywords: Indocyanine green; Oral ulcers; Photodynamic therapy; Rat; Wound healing.