The underlying causes for this disease are primarily poor sanitation and malnutrition. Although the causative organisms are common in many environments, this disease nearly exclusively affects extremely impoverished and malnourished children in tropical regions.<unk> is often reported as a sequela to acute necrotizing ulcerative gingivitis. Fusobacterium necrophorum and Prevotella intermedia are important bacterial pathogens in this disease process, interacting with one or more other bacterial organisms (such as Treponema denticola, Treponema vincentii, Porphyromonas gingivalis, Tannerella forsythia, Staphylococcus aureus, and certain species of nonhemolytic Streptococcus). Treatment of these organisms can help arrest the infection, but does not restore already-missing or disfigured tissue. Predisposing factors include: * malnutrition * vitamin deficiency (particularly deficiencies of Vitamin A and Vitamin B) * contaminated drinking water * immunodeficiency * poor hygiene, particularly oral * recent illness (especially acute necrotizing ulcerative gingivitis, measles, malaria, and severe diarrhea) * living in proximity to livestock
Noma 
Stoma 
Seroma
Mixed tumor
Neuroma
Hematoma
Myoma
Serous tumour