Main subjects
2.1. Formation of salivary secretion
2.2. Regulation of salivary secretion
2.3. Inorganic components of saliva and oral fluid
2.4. Mixed saliva proteins and enzymes
2.5. Non-protein organic compounds
2.6. Biologically active substances of saliva
2.7. Protective systems in the oral cavity
2.8. Gingival crevicular fluid
2.9. Formation of dental deposit and caries development
2.10. Dental calculus and inflammation of periodontal tissue
2.11. Saliva as an object of laboratory diagnostics
Saliva is one of the main fluids of the body. Salivary glands producing this secretion are assigned to the gastrointestinal tract glands along with the pancreas and the liver. Saliva performs the following functions:
► participating in cleansing the oral cavity from food remnants, dental deposit, and bacteria;
► neutralizing acids and alkali;
► providing the inflow of ions necessary for the maintenance of the structure of enamel hydroxyapatites;
► maintaining the species composition of the oral cavity microflora; forming a protective barrier composed of mucin, iron-containing proteins and WBCs;
► antibacterial, antifungal, and antiviral properties;
► participating in tooth pellicle formation, preventing calcium phosphate precipitation from supersaturated solution of saliva;
► moistening and softening solid food, facilitating bolus formation, and providing for the first stage of hydrolysis of food starch;
► regulating the secretion of digestive juices in the gastrointestinal tract.
2.1. FORMATION OF SALIVARY SECRETION
The fluid found in the oral cavity is not pure secretion of the salivary glands (ductal saliva), but a biological fluid called oral fluid or mixed saliva. Mixed saliva is a summary secretion of all salivary glands including desquamated epithelial cells (oral cavity detritus); the aggregate microorganisms forming the oral cavity microflora, the contents of gingival pockets, gingival fluid, the waste products of dental deposit microflora and WBCs migrating from mucosa, food detritus (remnants), etc. (Fig. 2.1).