MORPHOLOGICAL CHARACTERISTICS OF THE WOUND PROCESS OF THE ORAL MUCOSA, DEPENDING ON THE METHOD OF CONNECTING THE EDGES OF THE WOUND

Abstract

Purpose of the study. Compare and analyze the course of the processes of regeneration of the oral mucosa after joining the edges of the wound using suture material based on silk and n-butyl-2-cyanoacrylate adhesive com-position in the experiment.
Material and methods. The study was conducted in the department of experimental surgery of the National Insti-tute of Surgery and Transplantology. A. A. Shalimova of the National Academy of Medical Sciences of Ukraine on 24 outbred sexually mature male rabbits aged 16-18 months, body weight from 2260 to 3425 g (average weight 2843 ± 100 g) due to the similarity of the histolog-ical structure of the mucous membrane with the human one. Animals were divided into control and main groups of 12 animals each. Under intravenous anesthesia 3 ml of a 5% solution of sodium thiopental and 6 ml of a 1% so-lution of propofol and local infiltration anesthesia with a 2% solution of lidocaine (0.5 ml), using a scalpel blade No. 15, a cut longitudinal wound of 1.5-2.0 cm size was applied in length and 0.3-0.5 cm in depth on the mucous membrane of the upper jaw along the transitional fold of the vestibule of the oral cavity. In the control group, the animals were joined by the edges of the wound of the oral mucosa by applying knotted sutures based on coated silk (USP (EP): 5/0 (2), 0.75, cutting needle, “OPUSMED”). In the main group, each of the animals was joined by the edges of the wound of the oral mucosa using the n-butyl-2-cyanoacrylate adhesive composition “Histoacryl”.
On days 3, 7 and 14, the animals were removed from the experiment by an overdose of 5% sodium thiopental solu-tion. Tissue samples in the intervention area for histologi-cal examination were removed so that the wound channel with a deviation of 3 mm to both sides of the wound fell within their limits. Selected tissue samples were fixed in a 10% solution of neutral formalin for 24 hours, dehydrated in ethanol with increasing concentrations (from 70 to 100 ° C), enlightened in xylene for 30 minutes, kept for 2 hours at 37 ° C in a mixture of xylene and paraffin (1: 1), and twice in paraffin for 30 min at 56 ° C, compacted in paraffin, made histological sections 5 μm thick, which were stained with hematoxylin and eosin, picrofuxin ac-cording to van Gieson.

Photo documentation of histological preparations was carried out using a Leica ICC50 HD digital optical mi-croscope camera and morphometric processing using a video analyzer and the Paradise computer program de-veloped by the «Eva» research and production company.
Research results and discussion. In the main group of animals, acceleration of reparative processes in the wound was observed due to the rapid destruction of the adhesive masses, reliable connection of the edges of the wound, less tissue injury starting from 3 days. The in-flammatory response had a peak at 3 days, the intensity of which rapidly dropped to 7 days. On the 14th day, a uni-form connective tissue formation was observed, in places it did not visually differ from the intact sections of the oral mucosa. In the control group, after the use of suture material based on silk, a pronounced inflammatory reac-tion was observed on day 3, which lasted up to 14 days. The peak of inflammation in the control group was on the 7th day. On day 14, signs of inflammation decreased slightly, but were present due to a “foreign body” in the wound, the scar had signs of deformation and rose above the level of intact sections of the mucous membrane.
Conclusions. The use of the adhesive composition con-tributed to the rapid tissue repair in the surgical area, as evidenced by the signs of regeneration that were observed from 3 days, namely, the appearance of young collagen fibers and a thin layer of young granulation tissue, 16.05 ± 0.92 μm thick. The most optimal wound healing in the main group occurred on the 7th day after surgery, and was manifested by the acceleration of the formation of a gentle normotrophic connective tissue scar, as evidenced by the rapid change in the cells of the lymphocytic-macrophage series and partial restoration of the epitheli-al plate. Already on the 14th day, the intervention site did not differ from the surrounding intact sites. The ad-vantage of using the adhesive composition compared to suture material, starting from 7 days, is the absence of a “foreign body” in the postoperative wound.