Trench mouth (acute necrotizing ulcerative gingivitis or ANUG) is a severe yet reversible inflammation of the gums (gingiva). It is believed to be caused by an overabundance of normal bacteria coupled with poor hygiene; poor nutrition and/or vitamin deficiency; stress; smoking and, in severe cases, possible immune suppression. The Gram-negative spirochete, Borrelia vincentii is found in high numbers acting together with Fusobacterium species (Gram-negative aneaerobic) bacteria. Patients with the condition are often debilitated.
The term “trench mouth” originated after the many soldiers in World War I who were observed to have the condition. It is also known as Vincent’s Disease after the physician who first identified the disease. Trench mouth is now considered rare, but lower-grade variations of the condition probably exist.