Burning Mouth Syndrome? Opinions please.

I have always used flouride toothpaste. I just went back through my purchase history to see if I had tried a flouride-free option (I have tried a lot of things during this time and sometimes forget!) and I see I did try a flouride-free toothpaste. If it had helped the problem I definitely would have bought it again so it must not have made any difference. The toothpaste was by Green People, so a very good one.
I don't know how you've been faring with this; I stumbled across this link about lichen planus which you mentioned even though it wasn't as much of a problem as the burning mouth syndrome.