Saliva is a fluid secreted by the salivary glands that keeps the oral cavity moist and also coats the teeth along with mucosa. The salivary gland possesses tubuloacinar units, and these are merocrine. The functional unit of the salivary glands is the terminal secretory piece called acini with a roughly spherical or tubular shape. It also consists of branched ducts for the passage of the saliva and also plays an important role in the production and modification of saliva. Each type of duct is lined by different types of epithelia, on the basis of its location. Myoepithelial cells are contractile cells with respect to intercalated and secretory endpieces. Parotid, submandibular, and sublingual glands are the major salivary glands. The minor salivary glands are labial and buccal gland, glossopalatine gland, and palatine and lingual glands. Saliva plays an important role in mastication, speech, protection, deglutition, digestion, excretion, tissue repair, etc. Secretion stimulated in response to sympathetic stimulation will differ in protein and electrolyte from that due to parasympathetic stimulation. The concentration of saliva depends only on the rate of flow and not on the nature of stimulus. Saliva guides the clinician toward the optimal mode of treatment and guides the patient toward ultimate prognosis.
Part of the book: Histology