A small, shallow lesion that develops on the soft tissues in the mouth (inside the lips, cheeks, or under the tongue). Clinically known as Aphthous Stomatitis, they appear as white or yellow centers with a red border.
Unlike "cold sores" (caused by the Herpes virus), canker sores are not contagious. However, they can be extremely painful, making eating and speaking difficult.
Minor injury, immune system strain, hormonal shifts, or deficiencies in Vitamin B-12/Iron.
They are self-limiting, but healing can be aided by avoiding spicy/acidic foods, using saltwater rinses, or applying corticosteroid ointments.
Typically 7 to 10 days. If a sore persists longer than 2 weeks, it requires a biopsy to rule out oral cancer.