Re fluoride trays and rinses.
Initially I used a fluoride rinse (for 2-3 weeks into rads) and then I stopped Biotene mouthwash, regular brushes and regular toothpaste and switched to Biotene toothpaste and brush.
There was a time when everything burned, even water, the one exception was a baking soda/salt solution. Even so, I lowered the salt concentration to make this tolerable. I made gallons of the stuff with daily varying composition.....
There was also a pink concoction from the pharmacist.... which burned like hell and was never used.
It took a while before I went back to a regular brush and before could use mouthwash again. I still have problems with regular toothpaste. However, I expect that this should soon be reasonably tolerable as well. Depending on what you define recovery to be it can take a long time. This has to be put in context, you have to be alive to bitch about minor stuff like that!

M