A canker sore, or aphthous ulcer, is an open sore inside the mouth – usually on the inner cheek, lips, or tongue. Most are oval-shaped or round with a markedly white or yellowish center.…
A canker sore, or aphthous ulcer, is an open sore inside the mouth – usually on the inner cheek, lips, or tongue. Most are oval-shaped or round with a markedly white or yellowish center.…