Yes dental crowns can fall out. Crowns can fall out for a variety of reasons. If the crown has been in for a while then the usual reason why it comes out is because of the cement failing. This normally means that the crown just needs to be cleaned and re-cemented. The other common reason for a crown falling out after a period of time is a new cavity that has formed which loosens the crown.
However, regular check ups and cleanings at a dentist usually limit the possibility of a crown falling out by identifying particular issues before they happen. Hope this helps.
My best to you!
William F. Scott IV, DMD
Crowns can fall out. There are many reasons why crowns may fall out, such as tooth decay under the crown, tooth fracture, or something as simple of cement failure. However, the rates of crowns falling out in good strong healthy teeth is low, especially if the crown was made properly.