Histological evaluation of reparative regeneration of a wound created by laser irradiation with a wavelength of 445 nm in ablation mode

Background. In the world clinical practice for mucogingival surgery, an innovative laser technology is presented, the possibility of which is the preparation of the oral mucosa in a contactless way. Laser irradiation is generated by a diode semiconductor, has a wavelength of 445±40 nm, which corresponds to the blue color of the visible light spectrum. Scientific substantiation of the effectiveness and atraumatic nature of the use of laser irradiation with a wavelength of 445 nm as an alteration tool in surgical dental practice seems relevant.

Aim. The study sought to chart the morphological transformations undergone by healthy oral mucosa subjected to ablative laser irradiation at a wavelength of 445 nm.

Materials and methods. The study of the dynamics of reparative regeneration of the wound of the oral mucosa created by blue laser irradiation was carried out in an experimental study using the example of plastic surgery of the frenulum of the lower lip. The object of the study were 48 sexually mature male laboratory rats of the WISTAR line weighing from 180 to 250 grams. The mucous membrane of the vestibule of the oral cavity was prepared using a blue laser beam at a power of 0.7W and a continuous mode (CW).

Results. The minimum score for the severity of the inflammatory reaction was determined 25 minutes after the end of the operation and amounted to 1.1±0.7 points. The maximum score for reparative wound regeneration of 4.0±0.0 points was established on the 14th day of the postoperative period. The indicators of reparative tissue regeneration prevailed over the process of inflammatory reaction on the 7th day after the operation.

Conclusions. Semi-quantitative analysis of the histological picture of biopsy specimens allows for an objective comparison of the indicators of reparative regeneration with the indicators of the inflammatory reaction in the area of the surgical wound at different times of the postoperative period.

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