Tobacco smoke contains numerous chemicals with confirmed cytotoxic and carcinogenic effects. Saliva is the first biological liquid to be in contact with tobacco smoke in the oral cavity, which leads to changes in its composition. Tobacco smoke reduces saliva’s immune capacity affecting the amount of IgA and the antioxidant potential of saliva, which can result in an increased number of free radicals. The components of tobacco smoke contribute to changes in the composition of dental plaque and accelerate its mineralization by changing the amount of inorganic substances. Cigarettes smoking has also been proven to diminish the activity of some enzyme proteins present existing in saliva.

Key words: tobacco smoke, saliva, saliva properties.