what is a canker sore
canker sore is the name for a painful open sore in the mouth that is medically known as aphthous ulcer the sores are not contagious and are small shallow lesions that develop on the soft tissues in the mouth and gumscanker sores are more common in women than menanker sore is the name for a painful open sore in the mouth that is medically known as aphthous ulcer the sores are not contagious and are small shallow lesions that develop on the soft tissues in the mouth and gums canker sores are more common in women than men