Sialolithiasis (also termed salivary calculi, or salivary stones) is a crystallopathy where a calcified mass or sialolith forms within a salivary gland, usually in the duct of the submandibular gland (also termed "Whartons duct"). Less commonly the parotid gland or rarely the sublingual gland or a minor salivary gland may develop salivary stones. The usual symptoms are pain and swelling of the affected salivary gland, both of which get worse when salivary flow is stimulated, e.g. with the sight, thought, smell or taste of food, or with hunger or chewing. This is often termed "mealtime syndrome". Inflammation or infection of the gland may develop as a result. Sialolithiasis may also develop because of the presence of existing chronic infection of the glands, dehydration (e.g. use of phenothiazines), Sjögrens syndrome and/or increased local levels of calcium, but in many instances the cause is idiopathic (unknown). The condition is usually managed by removing the stone, and several different techniques are available. Rarely, removal of the submandibular gland may become necessary in cases of recurrent stone formation. Sialolithiasis is common, accounting for about 50% of all disease occurring in the major salivary glands and causing symptoms in about 0.45% of the general population. Persons aged 30–60 and males are more likely to develop sialolithiasis. Classification
The term is derived from the Greek words sialon (saliva) and lithos (stone), and the Greek -iasis meaning "process" or "morbid condition". A calculus (plural calculi) is a hard, stone-like concretion that forms within an organ or duct inside the body.
When minor glands are rarely involved, caliculi are more likely in the minor glands of the buccal mucosa and the maxillary labial mucosa. Submandibular stones are further classified as anterior or posterior in relation to an imaginary transverse line drawn between the mandibular first molar teeth. Stones may be radiopaque, i.e. they will show up on conventional radiographs, or radiolucent, where they not be visible on radiographs (although some of their effects on the gland may still be visible). They may also symptomatic or asymptomatic, according to whether they cause any problems or not. Signs and symptoms
Signs and symptoms are variable and depend largely upon whether the obstruction of the duct is complete or partial, and how much resultant pressure is created within the gland. The development of infection in the gland also influences the signs and symptoms. Pain, which is intermittent, and may suddenly get worse before mealtimes, and then slowly get better (partial obstruction). Swelling of the gland, also usually intermittent, often suddenly appearing or increasing before mealtimes, and then slowly going down (partial obstruction). Tenderness of the involved gland. Palpable hard lump, if the stone is located near the end of the duct. If the stone is near the submandibular duct orifice, the lump may be felt under the tongue. Lack of saliva coming from the duct (total obstruction). Erythema (redness) of the floor of the mouth (infection). Pus discharging from the duct (infection). Cervical lymphadenitis (infection).