Sorry to hear that @Shakalker - funnily enough - I had a couple of teeth go 'hot/cold' sensitive last night & am wondering if I've broken a tooth/filling! I started off on Letrozole, then Exemestane & now Arimidex!
Were you teeth checked out before you started chemo (even tho you stopped it early?) Some people's chemo can cause tooth problems.
Otherwise - do you think you may be grinding them in your sleep (or during the day?) This can cause problems as well - even breaking teeth.
All the best. Definitely worth getting a check up anyway!