idiomatically, to be made to cringe or feel sick by overly sweet or cheesy words/actions; to find something nauseatingly sentimental.
あの映画のラブシーンは甘すぎて、見ていて歯が浮いた。
The movie's love scenes were so saccharine that they made me cringe.
彼の過度な褒め言葉に歯が浮く思いがした。
His excessive flattery made me cringe.
あまりにもロマンチックなセリフは、人によっては聞くと歯が浮くことがある。
Overly romantic lines can make some people cringe when they hear them.
literally, to have one's teeth become loose or to get loose teeth.
歳をとって歯が浮いてきたので、歯科で治療を受けた。
My teeth started to loosen with age, so I received dental treatment.
転倒して歯が浮いたため、応急処置をしてもらった。
I fell and loosened a tooth, so I got first aid.