Definition
An aphthae represents a well-defined, either round or oval ulcer in the oral mucosa which is covered with a white-yellow pseudomembrane and mostly painful. It is surrounded by a margin and an erythematous halo. The most frequent aphthae are represented by the recurrent aphthous stomatitis (RAS) which affects 5-25per cent of the general population and is therefore plausible to also be the most common and recurrent inflammatory ulcerative condition of the oral cavity of healthy individuals. A localized burning or pain 24-48 hours in advance characterizes the typical prodromal symptom of RAS. The treatment is symptomatic.
If an aphthous ulcer is accompanied by symptoms like genital ulcerations, arthritis, adenopathy, fever or uveitis, a systemic etiology should be considered.
There are also some conditions which (indeed) have the same appearance like aphthae but actually are chronic diseases.