New discoveries have found exceptions to Mendel's basic laws, but none of Mendel's things have been proven to be flat-out wrong. Hail to the Father of Genetics ! The name is ma-ma-ma-ma-ma-Mendel.
Dental crowns should last on average from 10 to 20 years. Crowns are still subject to fracture and cavities, so it is important to take extra care in brushing and flossing around crowned teeth to prevent them from needing replacement too often.
A RealAge answered. Crowns, which cap a tooth that is too damaged to hold a filling, are expected to last about five to eight years. Many last much longer, though. Your dentist will check your crown at regular checkups, and if it is still working well, you may be able to keep it for many years. On the other hand, if you regularly grind your teeth, chew on ice, or bite your fingernails, your crown may need to be replaced even before five years is up.