Necrotizing ulcerative acute gingivitis (GUNA) is characterized by the presence of very aggressive bacteria that cause the destruction of the papilla (gum shaped peak between teeth) and bone. There may be formation of craters in the region Interdental. It can detect the presence GUNA gums bright red, bright and very painful. Bleeding gums is abundant and spontaneous and an unpleasant taste of metal is easily discernible.