B -- I had a fistula after radiation with exposed bone along my jawline. Five plastic surgeries couldn't fix it. Then I moved from California to Washington and my new cancer doc recommended hyperbaric oxygen. Seven weeks M-F, another minor surgery, and 3 more weeks of O2. Bingo!
I had to drive half an hour, take a 35 minute ferry ride to Seattle, hike 15 blocks, and sit in a pressurized tank for 2 1/2 hours each day. Best thing I've ever done! I met some wonderful people, my fistula healed, and my dry mouth went away. I can even eat spicy food again.
Hang in there. There's light at the end of the tunnel. :-)