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.
How long does soreness last after tooth extraction? One day to: 14 days is my standard answer. Depends on which tooth , the condition of the area prior to surgery, the surgical difficulty, your oral hygiene efficiency, your immune system/healing response and many other factors.