Corn is a small, hard, shiny thickening of the epidermis (outer layer of the skin). This thick growth presses on the dermis (deeper skin layer) and causes it to become thin and tender. Pressure and friction cause corns. Therefore, corns often develop over the joints of the toes of persons who wear shoes that do not fit properly. But corns may form anywhere on the body where pressure and friction injure the skin. A soft corn is one located between the toes. Here the thickened skin remains soft because it is constantly bathed with sweat.
Corn plasters remove the thickened epidermis and are used to relieve the pain of corns. Most plasters contain chemicals that soften the outer horny accumulation. To cure a corn, the things that caused it to form must be removed. Because of the danger of infection, paring corns with sharp instruments should be done only by a doctor.
