My teeth hurt REALLY bad at night. Had xrays everything looks fine. Sinuses also are fine. I also wear a mouth guard. It only hurts on top teeth. Any idea?

Night guard adjust. adjustment is needed. The greatest harm to the teeth and supporting structures occurs during para-function (clenching and bruxism), not during normal function. Ask your dentist for properly adjusting night guard in CR with point contacts in the posterior areas with anterior guidance providing immediate posterior disclusion. He/she knows what I am talking about.