Sialolithiasis of minor salivary gland. A challenging diagnostic dilemma.

Minor salivary gland sialolithiasis (MSGS) is a not uncommon oral mucosal disease. Its clinical appearance may mimic a mucocyst or other benign submucosal overgrowth. Stasis of saliva, which accompanies MSGS, usually results in minor salivary gland inflammation, with a chronic sialadenitis appearance. MSGS typically is a painless lesion but can become painful when the salivary gland parenchyma or excretory duct becomes infected, with or without pus. However, misdiagnosis of this condition is rather common, as the clinical appearance is asymptomatic. The most common location is the upper lip, and MSGS affects males and females, with a slight predilection for males. The sialolith causing MSGS may be obvious during surgical excision, as in the case reported. In other cases, sialolith may be absent or fragmented. Differential diagnosis includes mucocele, swelling due to local irritation like fibroma and diapneusia, chronic abscess of the oral mucosa, and neoplasms either benign (lymphangioma, pleiomorphic adenoma) or malignant. Histopathological examination is needed to establish clinical diagnosis.