Salivary gland disease

Salivary gland dysfunction affects the flow, amount, or quality of saliva produced. A reduced salivation is termed hyposalivation. Hyposalivation often results in a dry mouth condition called xerostomia, and this can cause tooth decay due to the loss of the protective properties of saliva.

Hypersalivation is the overproduction of saliva and has many causes.[5][6]

• Necrotizing sialometaplasia—a lesion that usually arises from a minor salivary gland on the palate. It is thought to be due to vascular infarction of the salivary gland lobules. It is often mistaken for oral cancer, but the lesion is not neoplastic.[2]

Infections involving the salivary glands can be viral or bacterial (or rarely fungal).

• Mumps is the most common viral sialadenitis. It usually occurs in children, and there is preauricular pain (pain felt in front of the ear), swelling of the parotid, fever, chills, and headaches.[2]
• Bacterial sialadentitis is usually caused by ascending organisms from the oral cavity. Risk factors include reduced salivary flow rate.
• Human immunodeficiency virus-associated salivary gland disease (HIV-SGD).[1]

Mucocele

• Mucocele — these are common and are caused by rupture of a salivary gland duct and mucin spillage into the surrounding tissues. Usually they are caused by trauma. Classically, a mucocele is blusish and fluctuant, and most commonly occurs on the lower lip.[7]
• Ranula — the name used when a mucocele occurs in the floor of the mouth (underneath the tongue). Ranulas may grow to a larger size than mucoceles at other sites, and they are usually associated with the sublingual gland, although less commonly they may also arise from the submandibular gland or a minor salivary gland.[7] Uncommonly, a ranula may descend into the neck rather than the mouth (plunging ranula). If small, the ranula may be left alone, but if larger and causing symptoms, excision of the sublingual gland may be indicated.
• Nicotinic stomatitis — the hard palate is whitened by hyperkeratosis caused by the heat from tobacco use or hot liquid consumption. This irritation also causes inflammation of the duct openings of the minor salivary glands of the palate, and they become dilated. This manifests as red patches or spots on a white background.[8]

• Sjögren's syndrome
• Graft-versus-host disease

• Post-irradiation sialadenitis
• Sarcoidosis—there may be parotitis alone or uveoparotitis (inflammation of both the parotid and the uvea of the eyes), which occurs in Heerfordt's syndrome.
• Cheilitis glandularis—This is inflammation of the minor salivary glands, usually in the lower lip, eversion and swelling of the lip.[7]
• Chronic sclerosing sialadenitis is a salivary gland manifestation of IgG4-related disease.[9][10]

• Frey's syndrome

• Salivary gland neoplasm

A salivary diverticulum (plural diverticuli) is a small pouch or out-pocketing of the duct system of a major salivary gland.[11] Such diverticuli typically cause pooling of saliva and recurrent sialadenitis,[12] especially parotitis.[13] A diverticulum may also cause a sialolith to form.[14][15] The condition can be diagnosed by sialography.[12] Affected individuals may "milk" the salivary gland to encourage flow of saliva through the duct.[12]

• Sialolithiasis - although several possibly coexisting factors have been suggested to be involved in the formation of salivary stones, including altered acidity of saliva, reduced salivary flow rate, abnormal calcium metabolism and abnormalities in the sphincter mechanism of the duct opening, the exact cause in many cases is unknown.
• Sialadenosis (sialosis) is an uncommon, non-inflammatory, non-neoplastic, recurrent swelling of the salivary glands. The cause is hypothesized to be abnormalities of neurosecretory control. It may be associated with alcoholism.[3][16][17]