The outcome varies depending on the cause of the ulcer. Many mouth ulcers are harmless and heal without treatment.
There are types of cancer, however, that may first appear as a mouth ulcer that does not heal. See: Squamous cell carcinoma
What to expect if I have Mouth ulcers  (Outlook/Prognosis)?
The outcome varies depending on the cause of the ulcer. Many mouth ulcers are harmless and heal without treatment.
There are types of cancer, however, that may first appear as a mouth ulcer that does not heal. See: Squamous cell carcinoma