Medically referred to as aphthous ulcers, canker sores are characterized by shallow lesions that affect your oral tissues. Remarkably similar to cold sores, canker sores are generally uncomfortable. But unlike cold sores, canker sores are typically isolated only to the soft tissues of your mouth and to the base of your gums.
Most episodes of canker sores do note require medical treatment, as it goes away on its own, within a 10-15 day period. Professional dental help is required, however, when an unusually prominent canker sore develops, or in cases when canker sores fail to heal even after 2-3 weeks time.
Canker sores usually appear as yellowish oval-shaped patches within mildly inflamed red borders. These patches usually appear on the inside surfaces of your mouth, on your tongue, cheeks, gums, and even on your soft palate.
People who are afflicted with canker sores typically feel a tingling or burning sensation, most commonly on their inner cheeks, the inside of the lips, and the surfaces of the tongue. Each patch of canker sore usually takes to 2-3 days to form and fully develop. These patches are most painful in their first 3 to 10 days.