Salivary Stones (Sialolithiasis)

How salivary stones form

You have three main pairs of salivary glands:

• Parotid glands in the cheeks, in front of the ears
• Submandibular glands under the jaw
• Sublingual glands under the tongue

Saliva contains calcium and phosphate. When saliva flow slows or becomes thick, these minerals can crystallize around debris and gradually build into a stone. Submandibular saliva is thicker and more alkaline, and its duct runs uphill, which is why most stones form there.

Risk factors

• Dehydration
• Reduced saliva flow from medicines such as antihistamines, diuretics, some antidepressants and blood pressure medicines
• Sjögren's syndrome and other causes of dry mouth
• Injury to the gland or duct
• Smoking
• Gout
• Men are affected more often than women, most often between ages 30 and 60

Symptoms

• Mealtime pain and swelling: the gland swells when you see, smell or eat food, then gradually goes down over 1 to 2 hours (salivary colic)
• A tender lump under the jaw or in the cheek
• A hard lump you can feel or see under the tongue at the duct opening
• Dry mouth or reduced saliva on one side
• A bad taste or gritty saliva

Signs of infection

A blocked gland can become infected (sialadenitis), causing:

• constant pain and swelling
• redness and warmth of the skin over the gland
• fever
• pus draining into the mouth, with a foul taste

See submandibular gland infection and parotitis.

Diagnosis

• Examination: the clinician feels the gland and the floor of the mouth, and may feel the stone. Pressing on the gland may show reduced or cloudy saliva from the duct.
• Ultrasound: the first imaging test, showing most stones and a swollen gland.
• CT scan: detects small stones and helps plan treatment.
• Sialendoscopy: a tiny camera passed into the duct can both diagnose and remove stones.

Treatment

Home care for small stones

• Drink plenty of fluids.
• Suck on sour candies or lemon wedges to stimulate saliva flow, which can push small stones out.
• Massage the gland from back to front toward the duct opening.
• Warm compresses on the swollen area.
• Pain relief: acetaminophen (paracetamol) or ibuprofen at the label dose.
• Good oral hygiene.

Medical treatment

• Antibiotics if the gland is infected.
• Removal through the mouth: a stone near the duct opening can be removed through a small cut under local anesthetic.
• Sialendoscopy: a minimally invasive procedure to remove stones from inside the duct with a basket or forceps.
• Lithotripsy: shock waves break larger stones into smaller pieces, available at some centers.
• Gland removal: surgery to remove the submandibular gland is reserved for large, deep or recurrent stones that cannot be removed otherwise. Parotid surgery is avoided where possible because of the facial nerve.

Outlook

Most salivary stones are successfully removed, and the gland often recovers its function. Stones can recur, so staying hydrated and maintaining saliva flow are important.

Prevention

• Drink enough water throughout the day.
• Review medicines that cause dry mouth with your doctor.
• Do not smoke.
• Practice good oral hygiene.

Frequently asked questions

What does a salivary stone feel like?

A salivary stone usually causes pain and swelling under the jaw or in the cheek when you eat, which settles an hour or two later. You may feel a hard, gritty lump under the tongue or a bad taste. If infection develops, pain becomes constant with redness and fever.

Can a salivary stone come out on its own?

Yes. Small stones often pass on their own, especially with plenty of fluids, sour candies to increase saliva, warm compresses and gentle massage of the gland toward the duct opening. Larger stones usually need removal.

How are salivary stones removed?

Stones near the duct opening can be removed through a small cut inside the mouth. Stones deeper in the duct can be removed with sialendoscopy, a tiny camera with instruments. Shock wave lithotripsy breaks larger stones. Gland removal is a last resort.

What causes salivary gland stones?

Stones form when minerals in saliva crystallize, often when saliva flow is slow or thick. Dehydration, medicines that cause dry mouth, Sjögren's syndrome, smoking and injury to the gland raise the risk. The submandibular gland is most often affected because of its thicker saliva and uphill duct.