Crowns and bridges used to be made of porcelain fused to metal also known as PFM. The common trend now is to use all porcelain crowns or crowns with a porcelain facing and a foundation made of zirconia. There are no metal parts in all-porcelain crowns, there is no risk of black lines across gum lines as the gums recede over time. This is a very common problem with PFM crowns.
Studies have shown that all porcelain crowns are as strong as the previously used PFMS. In our office we use the iTero 3D digital impression system to fabricate all our crowns. This ensures a precise laser scanned fit