Salivary gland
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The salivary glands produce saliva, which keeps the mouth and other parts of the digestive system moist. It also helps break down carbohydrates (with salivary amylase, formerly known as ptyalin) and lubricates the passage of food down from the oro-pharynx to the esophagus to the stomach.
There are three main pairs of salivary glands: the parotid, the submandibular and the sublingual glands. There are also many small glands in the tongue, cheeks, lips and palate, all of which consist entirely of mucous secreting cells (see Histology below) except for the serous glands of von Ebner, which reside within the moats surrounding the circumvallate papillae in the posterior 1/3 of the tongue, anterior to the terminal sulcus.
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Histology
Two types of epithelial cells in salivary glands produce either mucous or serous secretions. The parotid gland produces serous secretions. The submandibular and submaxillary glands contain a mixture of both types of cells, and produce a mixture of the two liquids.
Location of the glands
There are three salivary glands:
- The parotid gland is located near the ear (par- = next to, -otid = ear), and is the largest of the salivary glands.
- The sublingual gland lies underneath the tongue.
- The submandibular gland is a U-shaped structure, and lies beneath the ramus of the mandible (the angle of the chin).
Role in disease
- See mumps (parotiditis epidemica) and Sjögren syndrome.
Salivary duct calculus may cause blockage of the ducts, causing pain and swelling of the gland.
Tumors of the salivary glands may occur. These are usually benign, but may be malignant. The most common type of benign tumor is Pleomorphic adenoma, followed by Warthin's tumor.
Diagnostic investigation
A sialogram is a radiocontrast study of a salivary duct.
External links
de:Speicheldrüse es:Glándula salival fr:Glande salivaire it:Ghiandola salivare he:בלוטות רוק lt:Seilių liaukos mk:Плунковнa жлездa nl:Speekselklier no:Spyttkjertler pl:Ślinianka pt:Glândula salivar sk:Slinná žľaza fi:Sylkirauhanen