Dental crowns

1) What are dental crowns?

A crown is a type of dental restoration that fully cups over that portion of a tooth or dental implant that lies at and above the gum line. (An arrangement that's somewhat reminiscent of the way that a thimble fits over the end of your finger. See our graphics below.)

*A crown, in effect, becomes a tooth's new outer surface. In comparison, a dental filling just fills in or repairs a portion of its tooth.

A dental crown is permanently cemented to the tooth it has been made for. And once placed, a tooth-crown unit is created that functions, and is cared for, just like a natural tooth. As a rule, crowns are typically very durable and lasting restorations.

2) Why are crowns placed?

There are a several different reasons why a dental crown might be made for a tooth. Dentists routinely use them to:

1. Repair and strengthen damaged teeth.
2. Improve the appearance of teeth, including their color, shape and even apparent alignment.

While some treatment alternatives and options do exist, no other kind of dental restoration provides the exact same set of benefits and advantages as a crown.

*We cover crown applications (and the potential for their over diagnosis) in item #5 below.

3) Other terms for crowns.

Dental crowns are sometimes referred to as "dental caps," "tooth caps," or "porcelain jackets."

4) What types of materials are dental crowns made out of?

Crowns can be made out of:

• Porcelain (or other type of dental ceramic.)
• Metal (a gold or other metal alloy).
• A combination of dental ceramic and metal alloy (porcelain-fused-to-metal crowns).

The metal alloy used to make a crown may be precious, semi-precious or non-precious.

Base your crown choice on its characteristics.

Each kind of crown (due to both its construction type and the specific materials used to fabricate it) has its own characteristic advantages and disadvantages, and therefore its own set of most-suited applications. We've dedicated a page to this topic - What type of dental crown is best for your situation?

*As you'll learn when using the links both above and below, choosing a type of dental crown for you tooth may involve some compromise. Great crown strength and durability is sometimes sacrificed in favor of superior aesthetics, or vice versa, depending on the application.

Pictures illustrating the different types of crowns.

Use the following links to access informational graphics, like the ones above, which cover the following types of crowns:

*Dentist's sometimes have a bias (possibly based on convenience factors or profit margin) in regard to the kind of crown they typically recommend. You should allow your dentist to explain to you why they feel the type they have suggested makes the best choice for your tooth.

5) Reasons why dental crowns are placed.

A dentist might recommend placing a crown on a tooth for a variety of reasons but, in general, most of them will fall within one (or more) of the following basic categories:

1. Restoring or making changes with a tooth's shape.
2. Reinforcing a structurally compromised tooth.
3. Improving a tooth's appearance.

*A dentist's recommendation to place a crown is sometimes based solely on their judgment, as opposed to clear-cut clinical needs. Unfortunately, the fact that crowns can be quite costly, and therefore a substantial profit center for a dental practice, has the potential to influence this diagnosis.

Just as not placing a crown when one is indicated has associated risks, crown placement poses potential complications also. For this reason, this procedure should not be performed without reasonable justification. Let your dentist explain to you why they feel it is required. You may not fully understand all of their arguments (read our text below for further insight) but they should at least make some sense.

A) Restoring / changing the shape of teeth.

Since a cemented crown becomes its tooth's new outer surface, it's not too hard to understand how placing one can be used to restore or improve the shape of a tooth.

The advantage of a crown.

In some instances, it's conceivable that a dental filling might be placed as an alternative. A dental crown, however, offers a big advantage due to the way that it's constructed.

Crowns are fabricated in a dental laboratory (by a dental technician using molds your teeth). Dental fillings, in comparison, are built right in your mouth by way of your dentist placing the filling material directly upon your tooth.

It's easier to get the "perfect" tooth shape with a crown.

A dental laboratory technician gets the opportunity to simulate and examine aspects of your bite and jaw movements from a variety of angles, and then sculpt your dental crown so it has the ideal shape.

With a dental filling, the dentist has far less control over the restoration's final contours because it is often difficult for them to visualize, evaluate, or access to the tooth they're working on.

*Besides just appearance, shape factors can play a big role in maintaining proper dental health. Restorations that don't touch against neighboring or opposing teeth properly can allow tooth shifting. Weak contact with adjacent teeth can allow food to trap, which can lead to substantial risk for tooth decay and/or gum disease.

B) Strengthening teeth.

Dental crowns are routinely made for those teeth that have broken, have had large portions destroyed by tooth decay or have had root canal treatment. This is because beyond just restoring a tooth's shape, a crown can provide a reinforcing and strengthening effect too. (*This is especially true for all-metal and porcelain-fused-to-metal crowns. The strength and durability characteristics of all-ceramic crowns vary, so quiz your dentist about the track record of the type they plan to place for you.)

Fillings (amalgam or dental bonding) typically can't provide a substantial reinforcing effect for a tooth to the same degree. We discuss this topic in greater detail here: How does a crown strengthen a tooth? / When does one make a better choice than a filling?

C) Using porcelain dental crowns to improve the appearance of teeth.

Because dental crowns encase the visible portion of a tooth, any porcelain crown (all-ceramic or porcelain-fused-to-metal) can be used to enhance or idealize the cosmetic appearance of a tooth. (*It's usually easier for a dentist to achieve a superior aesthetic end result with an all-ceramic crown.)

If taken to an extreme, this technique can be used to radically improve the appearance of a person's smile. In fact, in decades past it was common to hear of movie stars who had had their teeth "capped." This simply meant that they got their perfect "Hollywood" smile by way of having dental crowns placed. (*Nowadays it's probably more common to hear about dental veneers being used to create the "perfect" smile. - See below.)

Placing crowns purely for cosmetic reasons may not be the best choice.

Actually, having your teeth "capped" just to improve their appearance can, in most cases, be a very poor choice. *For example, you can't necessarily expect that a crown's perfect look will last a lifetime. Here's an explanation why.

Dental crowns only make the best choice for making cosmetic changes in situations where they simultaneously serve other purposes, such as restoring teeth to their original shape or strengthening them.

At least consider the alternatives.

As a general rule, a crown shouldn't be placed solely to improve the appearance of a tooth if there is some alternative procedure that could just as well achieve the same end result.