Sialolithiasis is a disease associated with ectopic calcification, which often occurs in the submandibular gland. Foreign body theory is one of the hypotheses for the formation of a salivary calculus. Sialolithiasis caused by a migrated fish bone serving as a nucleus of a salivary calculus in a deep region is rare. We describe a case of sialolithiasis formed around a foreign body, which was a fish bone, in the transitional zone between the submandibular gland and duct.A 45-year-old woman consulted our hospital because of masticatory pain in the right submandibular region. Radiographic examination showed a pin-like radiopaque body in the same region. Under a diagnosis of sialolithiasis, the right submandibular gland was excised. The calcification, which was formed at the end of a fish bone,existed in the transitional zone between the submandibular gland and duct.
