Major-type Oral aphthous ulcer
Andreas Altenburg, Nadine El-Haj, Christiana Micheli, Marion Puttkammer, Mohammed Badawy Abdel-Naser, Christos C. Zouboulis. The Treatment of Chronic Recurrent Oral Aphthous Ulcers. Deutsches Ärzteblatt International. 2014;111:665-673. Figures used with kind permission from Springer-Verlag, Heidelberg.