What is a zirconia metal-free crown? zircon Metal-free crowns are actually a fixed prosthesis developed in the last decade as a preference for porcelains that do not have metal underneath, which we call full porcelain. It has a metal support inside it. zirconium There is a substructure that we call oxic. In fact, it has porcelain on it. This is used to be able to withstand the force very well, as well as to give better results in terms of aesthetics, as it is completely equivalent to metal supports. Zirconium It is actually a metal. It is found in nature as brown, but it is used in dentistry as oxidized zirconium oxide. It is aesthetic because it can transmit light. It is a biocompatible fixed prosthesis because it is very compatible with the gum. As a fixed prosthesis, it is also glued and forms a chemical bond with the tooth, making it a more durable and compatible prosthesis.