MedlinePlus Medical Encyclopedia: Canker sore (aphthous ulcer)

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Canker sore (aphthous ulcer)

Canker sores (Aphthous ulcers) are very common. Typically, they are a shallow ulcer with a white or whitish/yellow base surrounded by a reddish border. This ulcer is seen in an individual with AIDS and is located in front and just below the bottom teeth.

Update Date: 1/18/2007

Updated by: Benjamin W. Van Voorhees, MD, MPH, Assistant Professor of Medicine and Pediatrics, The University of Chicago, Chicago, IL. Review provided by VeriMed Healthcare Network.

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