Relevance. Oral fluid is an important indicator of health. Besides, it is the medium where the mechanical and chemical processing of food begins. Mixed saliva reveals the health condition of teeth, mucous membranes and organs of the oral cavity. Normally, the pH of the oral fluid at rest and during stimulation varies from 6.5 to 7.5. Changes in the pH of saliva in people using electronic cigarettes are the subject of active scientific research. POD systems, HQD, hookahs contain additives that can affect the acid-base balance in the mouth. Some studies show that the use of e-cigarettes can lead to an increase in the acidity (decrease in pH) of saliva. This is due to the presence of flavorings, acidic liquids, preservatives, and other substances that may be acidic in nature. The aim of the study is to evaluate and compare the pH of the medium in people using tobacco–containing alternatives. Materials and methods. In the course of the work, the dental status was assessed in 150 participants with at least one year of electronic cigarette smoking experience, as well as those who use classic cigarettes. Results. The analysis of the data showed that patients had a shift in the pH of the oral environment to the acidic side, which affects the condition of the hard tissues of the teeth and mucous membrane. Conclusion. The collection of mixed saliva from a dental patient plays an important role in preventive dentistry. This will help the patient and the doctor to monitor the effectiveness of oral hygiene, prevent the occurrence of caries and many diseases such as stomatitis, xerostomia, periodontal diseases.