Dried products such as paan masala and gutkha have higher concentrations of areca nut and appear to cause the disease. Other causes include: *Immunological diseases *Extreme climatic conditions *Prolonged deficiency to iron and vitamins in the diet
Oral submucous fibrosis
Dyskeratosis congenita
Zenker's degeneration
Van Buchem disease
Degos disease
Bromoderma
Keratomalacia
Kyrle disease