I have 7 crowns. Yeah, I have terrible teeth. Every once in a while one will come loose. My dentist tells me they should stay glued in place for 7 to 10 years, but I have some that have come loose sooner and some that have never come loose and I can always tell when one is about to come loose. Unfortunately carmel is one of my favorite candies, and also the most forbidden for crowns, lol. It'll pull one loose every time. So if you eat a lot of taffy, carmel or that kind of food, it will pull one loose real easy. Otherwise, you may want to find another dentist to make sure it was properly fit in the first place.