If the diagnosis is indeed recurrent aphthous stomatitis (RAS), there is, unfortunately, no permanent cure to it.
RAS appears to represent an immunological reaction by the body to various causes such as stress, trauma, nutritional deficiencies, allergies, genetic predisposition etc.
There are also certain medical conditions that may cause ‘aphthous-like’ ulcerations eg) anaemia, gastrointestinal diseases etc.
Thus the treatment would generally be to first rule out any potential systemic causes for the recurrent ulcers before the diagnosis of RAS is made.
For true RAS, the treatment would be:
1. Dietary advice if the ulcers are obviously related to certain types of food intake.
2. To practice good oral hygiene
3. Symptomatic treatment such as the application of Topical steroids eg) Orocort-E or Topical antimicrobials eg) Chlorhexidine mouthwash or Elugel which will help reduce inflammation and relieve the discomfort.
4. Systemic corticosteroids if all the above fails to help in the condition
That said, that are many other causes of ulcerations in the mouth also, some of which can be sinister if left undetected. I would thus advise you to get a checkup with a dentist and to go for follow-ups regularly so that the dentist would be better able to assess and monitor your condition. The right diagnosis would then lead to the right treatment modality for you!