There are several different types of material available for crowns, veneers and bridges, all with their own pros and cons.
In the past, crowns were functional but often not natural-looking (think gold or silver crowns on back teeth, or crowns with black gumlines on front teeth).
Modern materials combine strength and aesthetics. When needing a new or replacement crown, more and more people choose the metal-free options.
Emax crowns or veneers offer the best appearance of all the crowns we have, so they are commonly used for front teeth where this is important. They can be slightly translucent like natural enamel to give a lifelike appearance
Strength is very good. Emax crowns rarely chip or break. Veneers are thinner and so more prone to chipping
The crown is around 1.0-1.5mm thick, so tooth preservation is moderate.
Zirconia crowns give the best combination of strength and aesthetics, although they are not quite as natural-looking as the Emax crowns.
The strength is excellent. Zirconia crowns are able to withstand the high forces of chewing on molar teeth.
The crown is around 1.0mm thick, and Zirconia can be used for partial coverage crowns, allowing us to fully preserve any walls of enamel which are intact. This means tooth preservation is very good.
Porcelain-metal crowns have been around a long time and so have a long track record. The crown is made of 2 layers: The superficial porcelain is bonded to an interior metal layer.
The appearance can be very good, although porcelain-metal crowns do not share the translucency of Emax crowns. If the gum recedes, a dark line can sometimes be seen at the crown margin where the metal shines through.
The metal sublayer is very strong. However, the porcelain can sometimes chip away and expose the metal underneath (if this happens, the crown is still functional, but may not look or feel very nice)
The crown is 0.5-1.5mm thick, so tooth preservation is moderate.
Gold crowns have been around a very long time and the best track record of any crown material. The alloy is composed of several metals to give the best balance of strength, durability and accuracy of fit.
The only disadvantage of gold crowns is their appearance, and for this reason only we tend to fit fewer of these over time.
Gold crowns are very high strength
They can be made very thin, from 0.5-1.0mm, and Gold alloy can be used for partial coverage crowns, allowing us to fully preserve any walls of enamel which are intact. This means tooth preservation is the best of all crowns.