Although not news in any sense of the word, many people keep enquiring about the metal free option when it comes to getting dental crowns made. People just like the idea of getting crowns that do not have a surgical steel inner structure. This is interesting, as the structure is hypoallergenic and completely covered by tooth colored porcelain, so most people will never even be able to tell what kind of crown you have on at all. But still people are interested in a metal free option, which just shows us that people have some kind of weird, built in aversion to metal and metallic products, as far as medical things are considered.
The outer structure of a metal free crown is the same as any other crown, it is tooth colored porcelain, and the real difference, that makes these crowns metal free lie in the internal structure. A crown is basically an internal structure that is much like the internal structure of a house or a car, it is a metal outline, and a porcelain outer shell that is fused to this structure. The internal base of the crown is made out of zirconium oxide, a rather curious material. This mineral is never found in nature, and needs to be synthesized, but is derived from zircon, a metal that can be found in most mountains. This zirconium is the same material they use to make fake diamonds and other imitation gemstones. Zirconium oxide is the oxidised version of this mineral, a process that only happens in the dental laboratory. This is why these types of crowns are more expensive too, not only do you need to procure the minerals, but you also need to work with it in the lab as well.
The benefits from getting these types of crowns are purely visual and aesthetic, they do not last longer, do anything better, or give any sort of benefit that is not simply more pleasing to the eye. They wear out in about 5-10 years, just like normal crowns, but with the added benefit of looking like the cusps of real teeth. When someone has false teeth, crowns, you can tell when they smile, and a light source is nearby. This is because surgical sateelé is darker than zirconium, and thus the tooth will not look like real teeth at that point. BUt with zirconium the light passes through, and shines through a little bit, just as with real teeth. This way, they are completely indistinguishable from real, natural teeth. And that is the only difference between the two crowns.