Sialolithiasis, or the formation of sialoliths or salivary stones, typically occurs in the ducts of the submandibular and parotid glands of middle-aged adults. Pain and swelling are often among the first signs and symptoms. Obstructive sialadentitis, epidemic parotitis (mumps) and salivary gland tumors, should all be included in the differential diagnosis for sialolithiasis.