I want to get a crown done for one of my back teeth? I am a bit confused by the materials available - ceramic, porcelain, e-max and zirconia! What would you recommend?
At the risk of sounding too technical, e-max is lithium disilicate which is a type of ceramic/porcelain. Even though the terms porcelain and ceramic can be used interchangeably, porcelain sometimes refers to porcelain over metal crowns where there is a layer of porcelain over a “skeleton” of metal alloy. This was how crowns were done for many decades but with the advent of digital technology and CAD/CAM they are slowly becoming obsolete.
My recommendation for crowns for the back teeth will be monolithic zirconia - which means it's a single piece of zirconia without any added layers of ceramic or porcelain on top. Zirconia is at least twice and sometimes thrice as strong as most ceramics and usually will outlast any of them. They used to be a bit opaque in the past but are much more esthetic now and can be milled sometimes in the dental office in a matter of an hour or two with very high precision. Zirconia can also be made relatively thinner than ceramic crowns so there is less grinding of the tooth involved. People who grind their teeth at night would also be better off with zirconia due to the increased wear resistance.
An alternative would be emax crowns which can be placed on the premolars as they can be a bit more esthetic than zirconia due to their more transparent nature. An added advantage is that ceramics can be bonded to the tooth instead of cemented and that is a huge advantage if the tooth is severely broken down. This follows a concept called biomimetic dentistry where the crown is done with minimal grinding to the tooth and the missing parts of the tooth are bonded on like a jigsaw puzzle to complete the whole structure.
A decision is best made with your dentist after assessing the existing wear and tear on your teeth, whether or not you might be potentially grinding, your esthetic demands, the existing amount of remaining tooth structure and finally the position and visibility of the tooth in your mouth!