When are Dental Crowns Necessary?
The main purpose of dental crowns is to cover, strengthen, and preserve a damaged tooth while improving its overall appearance and alignment in the mouth. Here are some reasons why crowns are recommended:
- To save a tooth that has been so damaged and destroyed by decay that the remaining tooth structure is insufficient to support a traditional filling
- To protect a weak tooth from breaking
- To protect a cracked tooth from further damage
- To restore an already broken tooth or a tooth that has been severely worn down
- To cover and support a tooth with a large filling when there much tooth remaining
- To cover a severely discolored teeth
- To cover a dental implant
- To cosmetically modify a misshaped tooth
- To protect a tooth from breaking after root canal treatment has been complete
How are Dental Crowns Made?
Typically it takes two dental visits to fabricate a crown. Depending on the patient’s situation, Dr. Best first removes any decay, old fractured fillings, and weak or broken pieces of tooth. She then reduces the remaining tooth structure to accommodate the crown. Afterwards, a highly accurate impression is taken of the prepared and adjacent teeth. This impression is used to build a model of the tooth, which is sent to a special laboratory to create the crown. Dr. Best crafts a provisional crown and puts it in place to cover the prepared tooth while the permanent crown is being manufactured.
During the second visit, the new crown is cemented onto the prepared surface of the tooth. It fully covers the portion of the tooth above the gum line. In effect, the crown becomes the tooth’s new outer surface.
What are Crowns Made Of?
There are five different types of dental crowns:
- All-ceramic or all-porcelain dental crowns are used for restoring front teeth and other applications where esthetics is paramount. They can be custom color-matched and provide a better natural color than any other crown type. They are more suitable for people with metal allergies. However, they are not as strong as porcelain-fused-to-metal crowns and, on rare occasions may chip and break off. They may also wear down opposing teeth slightly more than metal crowns.
- Porcelain-fused to metal dental crowns can also be color matched to a patient’s adjacent teeth. Porcelain-fused-to-metal crowns look almost as much like natural teeth as all-ceramic crowns. They provide stronger bonds than all-porcelain crowns because the porcelain is connected to a metal base, making it extremely durable. However, on rare occasions, the crown’s porcelain can chip or break off. Occasionally, the metal underlying the crown’s porcelain can show through as a dark line, especially at the gum line. These dark lines can be even more pronounced if the gums recede. With this crown type there is more wear on the opposing teeth than with metal crowns. These crowns can be a good choice for front or back teeth. Note that the crown’s porcelain portion can also be susceptible to chipping or breaking.
- Gold dental crowns are alloys composed of gold, copper and other metals. These alloys are the most biocompatible and durable dental materials available. They do not fracture or wear away the opposing teeth, and they can last a lifetime. They require the least amount of healthy tooth to be removed prior to fitting. They are good choice for people who grind their teeth, and when esthetics are not important.
- Base metal alloy dental crowns are silver in color and made of non-noble metals that are highly resistant to corrosion. These exceptionally strong crowns offer the same benefits as gold crowns. They are best used on the back teeth where esthetics are not important.
- Stainless steel crowns are prefabricated and used for primary teeth in children. They require only one dental visit to put in place. They are cost-effective compared to custom-made crowns. When the primary tooth comes out to make room for the permanent tooth, the crown comes out naturally with it.
How Long Do Crowns Last?
With proper oral health care and periodic professional cleanings a crown can last a lifetime. A crown should always be treated like it is a natural tooth.
Only a dentist can remove it once it’s in place. To prevent damage to your new crown, avoid chewing hard foods, ice or other hard objects.
If your dental crown becomes loose or falls out …
Sometimes crowns can become loose or fall out. If this happens, save the crown and see Dr. Best right away. The crown can usually be re-cemented, providing the natural tooth structure under the crown is decay-free and solid.