Hi Killercheese,
I am sorry you have been having issues with persistent facial edema, it can be frustrating trying to deal with a diagnosis that does not seem to respond to treatment.
I am glad that you had a definitive diagnostic biopsy as it provides specific information for you and your doctor. "Oral facial granulomatosis" is also known as "Melkersohn Rosenthal Syndrome" and some people consider it to be a localized oral form of "Crohn's disease" as well.
Since you have not had adequate responses to the most common treatments and medications I suggest that you may want to speak with a specialist in either clinical oral pathology or oral medicine or an immuno-dermatologist. Any of these specialists should be able to provide you with additional information and will be up on the newest diagnostic tests and treatments.
You can also contact a Gastro Intestinal (GI) physician, I would suggest finding one who specializes in Crohn's disease, Ulcerative Colitis and Inflammatory Bowel disease. There are also some Allergists who may be able to help you although I would recommend that they be either hospital or university based.
Unfortunately the likelihood is that you may never be "cured". This does not mean that your condition cannot be managed. I strongly suggest that you try to see a specialist, either a dentist or physician, who has had experience dealing with conditions like this as they will most likely be able to help you manage your symptoms.
The American Dental Educators Association website may be a good place to start as you probably will want to work with a dentist or physician at a teaching hospital or university.
I hope that this helps and provides some guidance.
Dr. Gwen Cohen Brown