(From cancer, a spreading ulcer). Canker of the mouth; called also aphthea ser-jientes, librisulcium, gangrena oris, by Le Dran cheilo-cace. It is a deep, foul, irregular, fetid ulcer, with ragged edges, which appears upon the inside of the lips and cheeks; and is attended with a copious flow of offensive saliva.

This disease is seldom seen in adults, but it most commonly attacks children. When the ulceration begins at the inner part of the lip, it exhibits a deep, narrow, sulcatcd appearance, and quickly spreads along the inside of the cheek, which becomes hard, and tumefied externally. The gums are very frequently affected, the teeth are generally loose and diseased; matter is often found in the sockets, and abscesses sometimes burst externally through the check, the lip, or a little below the maxilla inferior: and it is not uncommon to see an exfoliation of the alveolar processes, or even of the greater part of the lower jaw. Among the children of poor people, where this disease is often neglected or mismanaged, a gangrene will sometimes supervene.

In order to the cure, it will be proper to remove any-diseased teeth or bones if possible; to prescribe a milk and vegetable diet, and to allow a prudent use of fermented liquors; to give the Peruvian bark, sarsaparilla, elm bark, and mineral acids.

External applications may be preparations of copper: a diluted mineral acid: burnt alum: decoction of bark, with borax, or tincture of myrrh. Sec Aphthae: also Pearson's Principles of Surgery, vol. i. p. 262.