A severe gangrenous process occurring predominantly in debilitated and malnourished children, especially in underdeveloped countries. It typically begins as a small vesicle or ulcer on the gingiva that rapidly becomes necrotic and spreads to produce extensive destruction of the buccal and labial mucosa and tissues of the face, which may result in severe disfigurement and even death. Various bacteria have been implicated in the etiology. (Dorland, 27th ed)