Superficial mucoceles of the oral mucosa.

Superficial mucoceles are innocuous vesicular lesions that have been mistaken for mucous membrane pemphigoid. Clinically they are asymptomatic, small, clear, tense vesicles that have a predilection for the retromolar pad area, posterior buccal mucosa, and soft palate. Microscopically they are subepithelial extravasations of sialomucin that occur at the epithelial connective tissue interface. Minor salivary gland ducts are present in the immediate vicinity of the lesions and are a clue to the correct diagnosis. Demonstration of sialomucin is diagnostic.