Ultrasonography (US) examination of a 53 year-old-man giving a history of swelling of his left sub-mandibular region during meals for 10 years, was performed and plain, oblique mandibula radi-ography was taken afterwards. On US, increase in size of the left submandibular gland, lobulated gland contour and heterogenous gland parenchyme was noticed and few echogenic structures with posterior acoustic shadowing, the largest having a diameter of 16 mm were seen in posterior part of the gland. Anterior to these echogenic structures, which were readily supposed to be sialo-liths, dilated ductal structures were seen presenting as anechoic, tubuler structures at the periph-ery of the gland. In plain, oblique mandibula radiography, soft tissue swelling in left submandibu-lar region was noticed and in this localization, some opacities most of which seemed to coalesce, largest one radiographically measuring 16 mm in diameter and totally measuring 34x16 mm were detected, providing to make the diagnosis of submandibular sialolithiasis. Though sialolithiasis of submandibular gland is more frequent than sialolithiasis of other salivary glands, submandibular stone of this size is a rare entity. It is apparent that, patient’s failure to seek medical help despite ongoing swelling complaints for 10 years, led the stone formation to continue and ended up with the formation of large, unusual left submandibular stone with a total, radiographically measured size of 34x16 mm. In this case, US and plain radiography were sufficient to diagnose submandibu-lar sialolithiasis.

Keywords: Plain Radiography, Submandibular Sialolithiasis, Ultrasonography