I hit my front tooht about 10 years ago, and it's ok.i am just wondering, if the tooth can go non- vital, even after that time?can pregnancy affect it?

You are OK: Trauma to a tooth 10 yrs ago would have shown up by now. Pregancy will not change that.

Yes: I've seen a tooth die 25 years after the trauma. Pregnancy has no affect!

Sort of ; no: The tooth can become symptomatic or show an infection in the bone even 10 years or more later. However, when the tooth actually became non-vital was probably in the few months past the accident. These types of situations are not that uncommon. Pregnancy had nothing to do with it.