Traditional crowns were always made of metal for strength. They were either solid metal, or they had a metal base with porcelain over the top. This worked pretty well for a long time, but had a few disadvantages. The porcelain layered over the top wasn’t strong, and had a tendency of breaking off in chunks. The porcelain also wore down the opposing teeth; after a decade the tooth on the opposite arch was often times worn flat. Also, the crowns weren’t very esthetic. The dark metal color would shine through the porcelain, giving it a grey shadow. This was most apparent at the gumline where people would often complain of a dark line. Many people also had biocompatibility problems where the gum would shrink away from the metal. And because nothing bonds chemically to metal, the tooth would have to be drilled down all the way to the gumline to get the crown to stay on. The right ceramic crown solves all of these problems.
A note about porcelain vs. ceramic: Those old metal-based crowns had porcelain layered over the top, as ceramic was not an option. Today’s metal-free crowns are usually ceramic. Ceramic is stronger than porcelain and wears down opposing teeth less. Most ceramic crowns are more esthetic than those metal based crowns, and they don’t have biocompatibility problems.
So you need a crown and you want it to be metal-free. You just need a ceramic crown, right? Not so fast! Most people should make sure they’re getting an e.max ceramic crown, and here’s why:
Some ceramic crowns (including e.max) can bond chemically to the tooth. The bond strength is so great that the tooth no longer has to be drilled down all the way to the gumline. Instead, just the top can be taken off the tooth, saving a lot of healthy tooth structure. Look closely at the above picture- the crown only goes halfway down to the gumline, as the bottom half of the tooth had no decay. At Enamor Dentistry, we believe in Minimally Invasive Dentistry, which is saving as much natural tooth structure as possible. e.max is by far the strongest ceramic crown that can be bonded to teeth.
Strength is very important in ceramic crowns. e.max is about four times stronger than the porcelain on those old metal-based crowns. Many dentists using Cerec same day crowns are making them out of materials only half the strength of e.max. These materials are cheaper than e.max and take less time to mill, but they often fracture after a few years of use. Compare that to e.max, which studies have shown have almost no breakage after 4+ years. Zirconia is the only ceramic crown material stronger than e.max, but it doesn’t bond to teeth. Teeth with zirconia crowns must be drilled down to the gumline, and are a good option for people that grind their teeth.
Esthetics are another reason to chose e.max crowns. They are more translucent and lifelike than zirconia crowns. As a matter of fact, most dentists use e.max for veneers due to its strength and beauty.
So if you need a crown, you’re question shouldn’t be, “Can I get a ceramic crown?” It should be, “Can I get e.max!?” If you need a new North Scottsdale dentist, Dr. Melander would love to tell you more about e.max crowns.