A crown, also referred to as cap, is a dental prosthesis used to fix severely damaged teeth. Crowns cover and protect the entire portion of your tooth sitting above the gumline. Essentially, placing a crown on tooth brings the broken tooth back to its original healthy form. Crowns seal off your teeth to protect them against fracture, cavities and other harmful traumatic forces which are exerted unto our teeth over time.
Whenever a filling is not strong enough to protect your tooth, a crown is usually the next step. Crowns have a wide variety of uses and fix many different dental problems. In fact, crowns are the most common dental procedure performed by most general dentists, aside from fillings and cleanings. Crowns protect teeth with cracks and fractures to prevent them from breaking even more. Placing a crown on a tooth at the right time can prevent the tooth from breaking more and avoids the need for a root canal or dental implant. Talking about root canals, almost all root canal treated teeth require a crown to re-enforce the tooth structure. Receiving a root canal weakens your tooth and a crown helps strengthen the tooth and restore its original condition.
Sometimes crowns are elective and placed primarily for cosmetic enhancement. Cosmetic crowns are used to fix chipped and discolored teeth. They can also fix crooked teeth thus eliminating the need for orthodontic work in cases with minor crowding or spacing. Even children occasionally require crowns on one or more of their baby teeth. Ever seen a child with a metal tooth in the back of their mouth? These are stainless-steel crowns placed on top of severely decayed baby teeth to protect them. As you can see, a crown is very useful in dentistry and has many, many different implications.
The most common types of crowns are made from gold, porcelain-fused-to-metal or ceramics.
Gold Crowns: In the old days, all crowns used to be made from a gold alloy. Gold is sturdy yet malleable, which makes it an excellent choice for fabricating dental crowns. However, gold has since fallen off in popularity and has been replaced with tooth colored material. This was primarily due to high cost of gold as well as patient’s preference for natural looking teeth over metals.
Porcelain-Fused-to-Metal (PFM) Crowns: PFM crowns consist of an inner layer of metal alloy and an outer layer of porcelain. The metal provides strength while porcelain provides natural-looking appearance. PFM crowns are a great option to restore damaged teeth, but they are not as durable nor esthetic as ceramic crowns. Porcelain tends to fracture and strip off the inner metal layer over time, especially in those who grind or have bite problems. Another flaw is that PFM crowns don’t look identical to teeth. The inner metal layer reflects light differently than natural teeth do. As a result, teeth with PFM crowns look dimmer and have a “fake” look to them. After a few years as your gums continue to recede, the inner metal layer starts to show through your gumline. This creates a purple-bluish line which appears right where your crown meets your gums. PFM crowns are also harder to clean as compared to ceramic crown which creates more bleeding around these teeth. Nevertheless, porcelain-fused-to-metal crowns have plenty of implication and we still perform lots of PFM crown. Just be aware that they are not as good as gold or ceramic crowns.
Ceramic Crowns: Ceramic is much stronger than porcelain, about 5 to 6 times sturdier. As a result, ceramic crowns are strong enough to handle bite pressure on their own and they don’t require any metal on the inside to strengthen them. Ceramic crowns are very sturdy, easy to clean and natural looking. They also age very well and maintain their appearance over the years. There are many different types of ceramic crowns, each with its own implication. Examples of ceramic crowns include zirconia, Lava, e-max and bruxzir crowns. E-max crowns look very natural and are ideal for restoring your front teeth. On the other hand, Bruxzir crowns are very sturdy and are ideal for restoring posterior teeth on patients with a heavy bite or grinding habits. If you want the best for your teeth, you should elect to go with ceramic crowns. Your dentist can help you choose the material that best fits your cosmetic and functional needs.
To learn more about how to properly care for your crown, click here.