I have had canker sores eevery since I can remember, my father gets them and so does my son. They are heritary. Apthus Ulcers. I have tried everything. Rotatational food allergy diet has been most successful. Although I still get them, the diet is extremely hard to follow. Dr. Lizak in Brunswick county, NC also has these sores. You must brush your teeth before going to bed. I have the wrong kind of bacteria in my stomach and I stress out easily, both causes.