Introduction. Liver diseases and pathology of the organs of mouth cavity are interconnected. Smoking, usually increases the manifestations of the underlying disease and affects the course. The aim. To investigate the effect of chronic toxic hepatitis of nicotine-dependent patients and of patients without a bad habit on their periodontal status.

Materials and methods. During the clinical examination of the oral cavity of 86 patients, the depth and incidence of inflammation of the gum were determined using the number of the Svrakov's number (SN); the conditions of hygiene of the oral cavity were estimated using the Silness-Loe (S-l) index; Periodontal Index (PMA) and Bleeding Index (PBI). General histomorphology was studied on drugs stained with hematoxilin-eosin and by the method of Gerlich and van Gieson.

Results. It is established that the indicator of SN had the highest value among patients of group II (2,15±0,13), it was probably (p < 0.05) higher relatively to the group I and comparison group. In the smoking patients with chronic toxic hepatitis, in spinous layer of epithelium was determinanted karyorhexis, karyolysis with the formation of cell debris; basal layer cell proliferation, acanthosis, angiogenesis. We detected damage to collagen and elastic fibers of the periodontal, wich correlated with the intensity and duration of the bad habit. In areas of pronounced alterative changes colonies of bacteria were discovered.

Conclusions. Thus, the results obtained in nicotine-dependent patients with chronic toxic hepatitis visualize damaging effect on the epithelium and weakening of the histohematic barrier of the oral cavity and promotes the reproduction and penetrationof pathogenic microflora into the underlying tissues.

Keywords: periodontium, chronic toxic hepatitis, nicotine-dependent.