Necrotizing ulcerative gingivitis is a periodontal disease commonly called trench mouth or Vincent angina. It is characterized by painful, erythematous, bleeding gums, malodorous breath, and necrosis and ulceration of connective gum tissue. Other signs and symptoms include malaise, fever, cervical lymphadenopathy, and the presence of fusobacteria and oral spirochetes. It occurs rarely in developed areas. It is most often found in developing areas, in association with poor nutrition and poor oral hygiene, with onset in childhood and adolescence. Other risk factors include smoking, impaired immune response, and stress. Untreated, it may progress to facial tissue necrosis, as in noma or cancrum oris.

Management involves several treatments including debridement, analgesics, antibiotics, and rinses.