Effect of laser biostimulation on cell proliferation in the healing of cutaneous surgical wounds in pigs

The objective of this study was to investigate the effect of low-level laser therapy (LLLT) on the proliferation of epithelial and connective tissue cells in the healing of incised cutaneous wounds in pigs. The experiment was conducted on 12 young pigs divided into four groups. Group I (undamaged skin) and group III (damaged skin) served as control. Group II - pigs with undamaged skin and group IV - pigs with incised wounds in the dorsal area were subjected to laser irradiation. Laser biostimulation was carried out using a CTL 1106 MX semiconductor laser in the continuous wave mode of operation at a wavelength of 810 nm and a maximum output of 100 mW. Following three weeks of observation, skin specimens were collected for histopathological analysis (HE), immunohistochemical detection of PCNA, and determination of apoptosis (TUNEL) and presence of mast cells (toluidine blue staining). Laser irradiation administered at E=8 J/cm for 1 min over a period of three weeks accelerated the proliferation of stratum basale cells, stimulated fibroblast proliferation, increased the number of mast cells in the wound area, and inhibited apoptosis in cells participating in the skin regeneration process.