Over the last decade, there has been an increase in illegal drug use and uncontrolled opioid abuse in patients with chronic pain, which is associated with unintentional trauma and is a major risk factor for tolerance and withdrawal, leading to overdose and death [1-5]. The attention of scientists in various fields of medicine is focused on the study of changes in organs and systems under the influence of drugs, in particular, both in clinical and experimental
areas [6-9]. In clinical studies it is indicated that when exposed to opioids there are signs of immunosuppression, which cause an increased risk of infectious diseases and the development of inflammation [5, 10, 11]. Toxic effects of drugs are manifested in all organs and systems, which
may have an indirect or direct effect on the organs of the oral cavity [6, 12-15]. The question of the role of bacterial flora in the etiology and initiation of periodontal disease is certainly actively studied as the improvement of microbiological methods and the accumulation of research results [16-19]. Today,
one of the main hypotheses remains that dental plaque microorganisms are a determining factor in the development and progression of the inflammatory process in the periodontium, which provoke the inflammatory process and directly affect the microbial status of the oral cavity [20- 23].There is also evidence that the role of microorganisms in the development of periodontitis is unclear, although some bacterial pathogens alone or as part of microbial groups may be particularly important [24]. Therefore, in order to prevent the development of periodontal disease and the occurrence of infectious foci in the oral cavity caused by bacterial biopellicle, it is important to determine the etiology and pathogenesis of this pathology in experimental animal models in order to further extrapolate these data to the clinic [25]. However, the relationship between the species and quantitative composition of the microbiota of tooth surface in the gingival margin and the development and progression of inflammation in the gingival mucosa under action of the opioid are controversial and needs further study using modern methods of microbiological research in the experiment.