Non-Metal porcelain crowns
There are many non-metal porcelains in current use made from zirconium or alumina. Your dentist decides on which non-metal porcelain to use after your examination.
Zirconium teeth are prefered for the posterior teeth as they are durable and provide an esthetic look whereas other non-metal porcelain structures are prefered for the anterior teeth.
Zirconiums have a durability degree of 900-1400 MPa whereas metal porcelains are durable approximately up to 800 MPa or less. The use of zirconium is also common for 3-4 unit bridges. As they have the same color as your teeth, you will not see gray reflections in the gum area.
Metal porcelain crowns
These crowns are used if there is tooth decay under the gums, too much enamel loss or if your teeth are broken. There are two types of crowns; metal and non-metal. Metal crowns are used largely on the posterior teeth due to grey reflections that can be seen on the gum line and their opacity
Non-metal porcelain restorations are mainly called esthetic porcelains.
Metal crowns reflect light shattering the feeling of depth and vitality. However, dentists have been able to make very thin metal porcelains via the spray process recently. Metal porcelains are more affordable compared to other porcelains.