OverviewMouth ulcers are caused by many disorders. These include canker sores, leukoplakia, gingivostomatitis, oral cancer, oral lichen planus, oral thrush, and similar disorders.
Review Date 5/14/2017
Updated by: Neil K. Kaneshiro, MD, MHA, Clinical Assistant Professor of Pediatrics, University of Washington School of Medicine, Seattle, WA. Also reviewed by David Zieve, MD, MHA, Medical Director, Brenda Conaway, Editorial Director, and the A.D.A.M. Editorial team.