Salivary gland stones (sialoliths) are hardened calcium deposits that form within your salivary glands or their drainage ducts. When a stone blocks the duct, the saliva produced during meals cannot drain freely, causing sudden pain and swelling on one side of your face or jaw.

Salivary gland stones are classified by location:

• Submandibular stones: the most common type (accounting for 80% of cases) because the glands under the jaw produce thick, calcium-rich saliva that must flow upward through a long duct.

• Parotid stones: less common (15% to 20% of cases) because the ducts leading from the cheek glands are wider and less prone to total blockages.

• Sublingual and minor stones: rare and typically very small deposits forming under the tongue or within the lining of the mouth.

Salivary gland stone symptoms are often cyclical, related to eating, and affect one side. Common signs include:

• Sudden pain or swelling of the affected gland at mealtimes, when salivary flow is stimulated but blocked by the stone

• A visible or palpable firm swelling under the jaw (submandibular) or in the cheek (parotid)

• Swelling that partially resolves between meals as saliva drains around the partial obstruction

• Dry mouth from reduced saliva production in the affected gland

• Difficulty chewing or swallowing if swelling is significant

• In complicated cases: fever, increasing pain, redness, and tenderness indicating acute sialadenitis (salivary gland infection) from bacterial superinfection behind the obstructed duct

• Pus discharge into the mouth from an infected gland

Salivary gland stones develop from the precipitation and accumulation of calcium salts within the salivary ducts. Contributing causes include:

• Altered salivary composition: high calcium and phosphate concentration in saliva, particularly in the submandibular gland, promotes crystal nucleation and stone growth.

• Reduced salivary flow: from dehydration, certain medications, or systemic conditions allows saliva to stagnate in the duct, increasing the concentration of minerals and promoting stone formation.

• Medications causing dry mouth: including antihistamines, antidepressants, antihypertensives, and diuretics significantly reduce salivary flow and are among the strongest risk factors for stone formation.

• Dehydration: reduced fluid intake concentrates saliva and promotes mineralisation.

• Gout and hyperuricaemia: elevated uric acid is associated with salivary gland stone formation through urate deposition in salivary tissue.

• Hypercalcaemia: elevated serum calcium from hyperparathyroidism or other causes increases the calcium content of saliva, promoting stone formation.

• Sjögren's syndrome: chronic autoimmune salivary gland inflammation alters duct architecture and salivary composition, predisposing to stone formation.

• Previous salivary gland infection or injury: causes ductal scarring that promotes stone formation and impairs drainage.

Salivary gland stones are detected through imaging of the head and neck soft tissues, with blood tests identifying the systemic conditions most commonly contributing to their formation.

Head and Neck MRI Elfcare’s full-body MRI can identify salivary stones, swollen ducts, and gland infections as part of routine imaging, and is particularly useful for visualizing ductal dilation and gland tissue changes, offering a physical explanation for jaw swelling or facial pain that might otherwise be misdiagnosed as a dental problem.

Blood tests identify systemic conditions contributing to stone formation and assess for complications. Relevant markers in Elfcare's panel include:

• Calcium and albumin-corrected calcium: elevated serum calcium from hyperparathyroidism or other causes increases salivary calcium content and promotes stone formation

• Uric acid: elevated in gout and hyperuricaemia, associated with salivary gland stone formation through urate deposition

• CRP and full blood count: elevated CRP and white cell count indicate active sialadenitis requiring antibiotic treatment

• Glucose and HbA1c: diabetes impairs immune function and salivary gland health, predisposing to recurrent infections

• TSH: thyroid dysfunction can affect salivary gland function and is relevant to the broader metabolic context

Why early detection matters

Salivary gland stones identified early, before they have caused recurrent infection or significant gland damage, can be treated with minimally invasive techniques including sialendoscopy, a thin endoscope passed into the salivary duct to locate and remove the stone while preserving the gland. Repeated episodes of obstruction and infection cause progressive fibrosis and functional loss of the affected gland, eventually making gland-preserving treatment impossible and leaving surgical gland removal as the only option. Identifying and correcting the underlying systemic conditions driving stone formation, particularly hypercalcaemia, gout, and medication-related dry mouth, reduces the risk of recurrence after stone removal.

How Elfcare can help

Elfcare's full body MRI covers the head and neck soft tissues as standard, directly imaging the salivary glands and their ducts, identifying stones, ductal obstruction, and gland inflammation. For a condition that is frequently misattributed to dental problems or dismissed as recurrent swelling, this structural assessment provides a precise diagnosis and the basis for appropriate management.

Our blood panel covers calcium, uric acid, CRP, glucose, and relevant inflammatory markers, identifying the systemic conditions most commonly driving stone formation and the complications of obstruction.

If our MRI or blood tests identify salivary gland stones or related findings, we take care of further diagnostics or refer you to the appropriate specialist.