Sialolithiasis (sigh a lo THIGH a sis) is a condition where tiny salivary stones form in the glands. The stones, called sialoliths, are made of calcium. Some stones do not cause any symptoms, but some stones block the ducts. The saliva flow is partially or completely stopped.he three major salivary glands are the parotid gland, submandibular gland (also called the submaxillary gland), and sublingual glands. Saliva drains into the mouth through small tubes called ducts.
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