It is always a very difficult question to answer when a patient asks "How long will a crown last?" because there are so many factors that go into that answer. A well prepped, fabricated, and cemented crown can last well over 20 years. At this point in my career, I have patients with crowns in their mouths that I placed in the late 1990's, and they have had no problems. The strongest (non metal, ie gold) crown would be a full zirconia crown. Many laboratories can fabricate beautiful full zirconia crowns, that are incredibly strong, and almost impossible to fracture, but there is a tradeoff. Your biggest tradeoff is aesthetics. Zirconia crowns tend to be opaque, and do not transmit light as well as a natural tooth, or other porcelain/ceramic materials. It also does not have the same bond strength to the tooth as other materials. I personally would not place a zirconia crown on a front tooth unless you are a severe bruxer (grinder). I prefer to use vita porcelain or empress porcelain on front teeth, and do them every day on my patients. You will get excellent aesthetics, with very natural looking results, but it is a little bit weaker than zirconia. In the end, if you are not a grinder, and don't open things with your teeth/bite your nails, I would recommend the vita/empress all porcelain (ceramic) crown. If you would like some extra insurance on the longevity of your crown, ask your dentist to make you a hard acrylic nightguard. There is no reason a properly done crown should not last you 20+ years. Best of luck...