Necrotizing Periodontal Diseases
In 1999, the American Academy of Periodontology classified the seven types of periodontitis and included necrotizing periodontal diseases in these classifications. Necrotizing periodontal diseases appear at varying levels of severity, ranging from necrotizing ulcerative gingivitis to necrotizing ulcerative periodontitis, necrotizing stomatitis, and the most severe and often fatal cancrum oris. This classification of necrotizing periodontal diseases usually has a sudden onset and therefore may be characterized as acute. Periodontitis is the most severe form of periodontal disease, which is also known as gum disease. This disease is characterized by inflammatory conditions that adversely affect the periodontium, or the tissues that surround and support the teeth. In its advanced forms, periodontitis can lead to bone loss, recession and detachment of the gums, and lost teeth, and it is also characterized by bad breath.
Necrotizing ulcerative gingivitis and acute necrotizing ulcerative gingivitis are common and are not contagious; though they are classified separately, this disease most frequently appears in its acute form. If acute necrotizing gingivitis is not treated promptly and properly, it may become chronic and recur episodically. In developing countries, acute necrotizing gingivitis is most seen in undernourished young people. In developed countries, acute necrotizing gingivitis appears mostly in young adults who are predisposed to the disease because of stress, sleep deprivation, improper oral hygiene, smoking, immunosuppression, or inadequate nutrition. Because people in a shared population may share predisposing factors, acute necrotizing gingivitis may resemble an epidemic and appear contagious; it is sometimes referred to as trench mouth, because it affected multiple frontline soldiers in World War II, for example. It is not contagious, however, and is attributed only to these shared predisposing factors. The disease is primarily characterized by bleeding and pain in the gums and ulceration or decay of the gums and tissue between the teeth. Other symptoms may include swollen lymph nodes, halitosis, and malaise.
Necrotizing ulcerative periodontitis, which also appears in an acute form, is an infection that has further progressed and led to destruction of the ligaments that hold the teeth in place, affecting the tissues of the gums and the periodontal and alveolar ligaments. When necrotizing ulcerative periodontitis progresses into the tissues beyond the gums and ligaments, it becomes necrotizing stomatitis. These tissues include the mucogingival junction, which is the area where the firm tissues that surround the teeth meet with the fragile, freely moving tissues on the insides of the cheeks and on the floor of the mouth. At this point, the disease has progressed considerably and shares many characteristics with cancrum oris.
Cancrum oris, which is also called noma, is a thoroughly destructive infection that affects not only the periodontium but also the entire mouth and the face. In the modern world, this disease is seen most frequently among severely malnourished children in developing countries. It often disfigures the face and is usually fatal. It is believed that cancrum oris arises from untreated cases of necrotizing ulcerative gingivitis, though this has not been clinically proven. It is also not common for untreated cases of necrotizing ulcerative gingivitis or necrotizing ulcerative periodontitis to progress into these more severe forms, even if left untreated, due to other contributing factors that may contribute to necrotizing stomatitis and cancrum oris.