FEATURES OF MORPHOLOGICAL RECONSTRUCTION OF PARADENTIUM ON THE BACKGROUND OF SIX-WEEK OPIOID ACTION WITH FURTHER WITHDRAWAL AND COMPLEX TREATMENT DURING FOUR WEEKS IN THE EXPERIMENT.

This study aimed to research the features of microscopic reorganization of paradental tissues under six-week exposure to the opioid analgesic nalbuphine, and under the conditions of its four-week withdrawal and medicinal correction with pentoxifylline and ceftriaxone in the experiment. The study was performed on 22 male rats, weighing 160-255 g, aged 4.5-7 months. Animals were administered nalbuphine for 6 weeks, with a gradual increase in dose (0.212-0.252 mg/kg). after period of four-week withdrawal of nalbuphine, a medicinal correction was performed using pentoxifylline and ceftriaxone (2.86 mg). The complex treatment made after 4-week period of opioid withdrawal, which was administered to animals during 6 weeks, led to the healing of ulcers, which showed signs of reepithelialization. The structure of collagen fibers of the lamina propria of the gingival mucosa was partially restored, the signs of angiogenesis were determined. Signs of mucoid edema and reduction of hypervascularization, stasis, erythrocyte aggregation in the lumen of blood vessels were observed in the periodontium, what helped to improve microcirculation and restoration of the structural organization of the paradentium. The use of pentoxifylline and ceftriaxone after period of 4-weeks withdrawal of opioid, which was administered for 6 weeks at the beginning of the experiment, prevented the rapid progression of inflammatory-dystrophic process and caused a protective effect on paradental tissues.