sorry to read you have to be here, but glad you found it.
My doc told me I was genetically predisposed as well, but I did smoke on and off for 7 years, total of 4...but they say that didn't cause it...I don't believe that, lol.
I am glad you are able to still tolerate eating and drinking! That's great. I wasn't able to after my 4th treatment.
Hopefully you can continue to do this throughout your whole treatment!
I am surprised they didn't tell you to do mouth stretches before and during your treatment. Mine and most that I have heard of give you stretches and advise you start them before going to treatment and continue them throughout.
The one that was most effective for me was open mouth as big as i can and hold it there to the count of 5, and repeat about 10 times and do that at least 3 times a day, but I did it probably 5 or more times a day, and really don't have much of an issue opening my mouth anymore.
I am a year out of radiation...still can't tolerate acidic or spicy food and still have somewhat thicker saliva, and dry mouth when i wake up.
Everyone experiences different things...so my results may not be the same for you.
As for the tooth issue....my dentists and oral surgeons do whatever they can to keep me from losing or having to have a tooth pulled, and they said it will be like that for the rest of my life. They said if I do end up losing one or have to have one pulled, I will more then likely have to endure hyperbaric oxygen treatments to help me heal because radiation attacks the blood vessels in your jaw, which make healing a lot harder if not impossible.
Hope the rest of your treatment comes quickly and with no more complications and you are able to continue eating and drinking throughout!