Regurgitate? I clearly can't expect you to be honest, or logical, but do you mean to honestly say you never at least once in your life had a food particle stuck in your teeth that later somehow worked its way out?
Corn on the cob, maybe popcorn. While I’m eating. Not hours later.
Does Ted Cruz not brush his teeth? How long was this unknown food particle stuck in there? He’s not going to have a tooth left in his head if he’s being as cavalier about personal hygiene as you appear to believe.