COMPARATIVE DESCRIPTION OF HEALING OF SURGICAL WOUNDS IN THE ORAL MUCOSA AND SKIN OF PIGS. LIGHT OPTICAL AND ELECTRON MICROSCOPIC EXAMINATION

Objective: to study the specific features of the structural elements of the hard palate and skin in the healing of incised and sutured wounds at the stage of hemostasis and inflammation in pigs.

Materials and methods. Nine piglets weighing 35–40 kg were taken for an experiment. 2.5–3.0-cm rectilinear incisions (surgical wound models) were made in the back skin and hard palate. Three skin biopsy specimens and 3 hard palate mucosal biopsy specimens were taken for morphological examinations in each experimental series (control, 6 hours and 3 and 7 days postsurgery). The electron microscopic material was fixed by an in situ immersion method and then processed by the conventional procedure. Semi- and ultrafine sections were examined under a Latimet light microscope (Leica) and a JEM-1400 electron microscope (JEOL), respectively, at an accelerating voltage of 80–120 kW.

Results. A rapid decrement of inflammatory processes in the incised and sutured wounds in the early stages of healing results in delayed cleansing of damaged structures and fibrinoids from the wound surface compared to those in the heard palate mucosa. So formation of mature skin granulation tissue begins on day 7 rather on day 3.

Conclusion. The differences in the phases of hemostasis and inflammation affect the further phases of reparative regeneration (proliferation and scar formation), which may lead to a difference in the development of postoperative wound scar tissue. 

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