health

The doctor or dentist will usually diagnose canker sores on the basis of
their appearance inside the mouth. If the sores do not heal or become
more severe, a sample of tissue may be taken to check for other possible
mouth disorders. Patients with AIDS, for example, may have an infection
in the mouth along with the canker sores. In a very few cases, a sore
that does not heal is a symptom of cancer.