Saliva plays an important role in oral health regulation and salivary diagnostics is now entering to the modern dentistry

Аннотация

Saliva plays an important role in oral health regulation and salivary diagnostics is now entering to the modern dentistry. In modern medical literature there are many papers on methods of diagnosis of general diseases by analyzing the mineral composition and properties of saliva. Some properties of saliva are sensitive indicators of serious systemic disorders and conditions of the body. The article contains data on the saliva of children with different somatic diseases. Key words: saliva, reduction of salivary secretion, mineralizing properties of saliva, dental status, systemic disorders. Saliva is a complex biological fluid, which is a complex secretion of the major and minor salivary glands. Being a physiological "external" environment for the teeth and the mucous membrane of the oral cavity, saliva provides lubrication of the organs and tissues of the mouth, moistens dry food, participates in the digestive process, performs trophic and protective functions [44]. This small-volume secretion plays a vital role in maintaining the normal functioning of all organs and tissues of the oral cavity. Oral fluid consists of mixed saliva and organic impurities. Mixed saliva consists of the total secretion of the parotid, submandibular and sublingual salivary glands, as well as small salivary glands of the tongue, floor of the mouth and palate. Organic impurities are represented by microbial, epithelial cells, serum components, blood cells, food debris, etc. Oral fluid is 99% water and only 1% mineral and organic substances, which determine its unique properties and functions. Impaired salivation can negatively affect the patient's quality of life. Adequate knowledge of saliva and its role in ensuring oral health is necessary for dentists to promptly identify and treat possible deviations from the norm. As Claude Bernard noted, we recognize the functions of an organ by identifying the consequences of its absence. The important role of saliva is best demonstrated in those patients in whom salivary secretion does not actually enter the oral cavity. Hyposalivation and xerostomia are increasingly common in the population of developed countries, where the average life expectancy is higher. Decreased salivary secretion is observed in Sjogren's syndrome, diabetes mellitus, in the condition after radiotherapy of the head and neck, in the treatment of oncological diseases, with a decrease in the chewing function, and mental disorders [48,49]. Hyposalivation entails a decrease in the cleansing ability of saliva, a deterioration in its antimicrobial, buffering, and remineralizing functions, and, as a consequence, a decrease in its caries-protective properties. The less saliva is secreted, the lower its buffering capacity and 51 ILM-FAN VA INNOVATSIYA ILMIY-AMALIY KONFERENSIYASI in-academy.uz/index.php/si the longer the pH value of the biological film remains in the acidic region after each meal. This significantly increases the risk of developing caries [42]. Clinical review The condition of tooth enamel is largely determined by the characteristics of oral fluid. The period of enamel maturation after tooth eruption is the most important stage in the formation of its resistance or caries susceptibility [26]. Oral fluid plays a vital role in maintaining the physiological balance of de- and remineralization processes. Enamel and dentin do not dissolve in saliva because it is supersaturated with calcium, phosphate and hydroxyl ions. These ions are the basis of apatite, from which enamel prisms are built. The degree of mineral supersaturation is even higher in dental plaque, especially in the extracellular liquid phase, which is in direct contact with the tooth surface. In the dynamic equilibrium of the exchange process, the supersaturation of saliva provides a barrier to demineralization and is the driving force of remineralization. The supersaturated state of saliva is overcome only when the pH of dental plaque falls below a critical value [16]. The pH of dental plaque decreases mainly after the consumption of sugars. Saliva, in turn, acts as a buffer due to the phosphates, bicarbonates and proteins it contains, neutralizing the effect of acids on the tooth. It has been found that stimulated saliva has a higher pH value compared to unstimulated saliva [35]. In unstimulated saliva, the bicarbonate level is low, whereas with an increase in the rate of salivary secretion, the bicarbonate concentration and the buffering capacity of saliva increase significantly. The average pH of unstimulated saliva is 6.75 (from 6.2 to 7.4) [32, 39]. At a very low secretion rate, the pH can drop to 5.3, and at a high rate, it rises to 7.8. The pH value of saliva changes during the day: in the morning, the indicator is significantly lower than in the middle of the day, increases in the evening, and then decreases again during sleep. The indicator also changes in connection with food intake: the pH increases during meals due to an increase in the rate