Q. Hi a got a all porcelain crown on one of my front teeth like a year ago.i had got a root canal before i got the crown because after the root canal my tooth turned really dark.so after i got the crown everything was fine,it matched my other tooth next to it.until now,a year later, i’ve noticed that the crown statred getting dark and i think it might be the tooth under it.i am not sure what to do because they had told me that the crown was not going to change color.what do i have to do???please help!!