Oh, wow, I have this, too, and I am also three years out. My doctors have no clue, either. Another poster referred to it as "football tongue". It never lasts long, a minute or two at the most, and I haven't been able to pinpoint a reason, either. Two of my doctors thought that it almost sounded like an allergic reaction, but there isn't anything that would seem to trigger it. I would guess that it is just another example of "the gift that keeps on giving" - radiation.
