Salivary duct stones are accumulations of calcium and phosphate crystals in one of the salivary ducts. These include the parotid, submandibular, or sublingual glands. The parotid glands lie just behind the angle of the jaw, in front of the ears. The submandibular and sublingual glands are deep in the floor of the mouth.

What is going on in the body?

Saliva is formed in response to smell and taste stimuli. It provides a healthy environment for the teeth. Saliva also helps break down complex starches. When the water content of saliva is reduced, the calcium and phosphate in the saliva can form a stone.

What are the causes and risks of the condition?

Stones are more likely to form when the water content of saliva is lower. A person who is dehydrated is at higher risk. Certain medicines also predispose someone to stones. These include antidepressants, antihistamines, and diuretics.

Certain diseases cause thickening of the saliva and increase the risk for stone formation. One example is Sjogren syndrome, which causes dryness of the mouth and other mucous membranes. In some autoimmune disorders, the body attacks its own salivary glands. This thickens the saliva and forms stones.