I am 4 1/2 years out from BC surgery, chemo and radiation. In that time I have had 3 fillings fall out. Also have had to have 3 caps due to teeth breaking. Oncologist never said to watch for possible issues but dentist said all the treatment and AI causes teeth to dry out, shrink (causing old fillings to fall out) and get brittle (teeth breaking). I have always had regular checkups and cleanings every 6 months. After my dentist retired 3 years ago I was very fortunate to find a new dentist with a lot of the latest techniques. Has been able to find some minor cracks within the last year and have sealed or filled them immediately. Dentist thinks all is slowing down. But says we need to be vigilant and watch. I guess it is just another side effect that we are not told about ahead of time!