Porcelain veneers and dental crowns: What is the difference between them? When is each used?
When explaining the details of each of our Dental Makeovers, we often suggest that either dental crowns or porcelain veneers might be used to create the results that we've illustrated in the case's "after" picture.
And although it is true that they can both create an identical cosmetic end result, these two types of restorations are very different and therefore have different applications.
What's the difference between a dental crown and a porcelain veneer?
A fundamental difference between veneers and crowns is how much of the tooth they cover over.
Details about crowns.
As another major difference, and as the illustration to the right shows, crowns are also much thicker than veneers. Here's the how and why in regard to that.
Dental crown placement requires a significant amount of tooth trimming.
When a dentist prepares a tooth for a crown, it's reduced in size and shape to a tapered nub.
The idea is, when the crown is cemented, it becomes the new outer surface for the tooth. (That's why a crown can be used to give a tooth a new color as well as a new shape.)
The amount of tooth reduction that's needed is usually on the order of at least 2 millimeters (2 mm is just slightly more than one sixteenth of an inch). There can, however, be reasons why a dentist may need to trim even more that that in some regions.
This measurement is based on the fact that most crowns need to be at least 2mm thick. That varies, however, depending on the type of materials that it's made out of (porcelain, metal or a combination of both).
How do porcelain veneers differ from dental crowns?
In comparison to crowns, porcelain veneers just cover over the front side of a tooth.
Porcelain veneer placement requires very little tooth grinding.
As mentioned above, crowns and porcelain veneers also differ by way of their comparative thickness. Porcelain veneers are wafer thin. They usually measure 1 millimeter in thickness or less, as opposed to a crown's 2 millimeters or more.
This means that significantly less tooth grinding is required when veneers are placed. (Less reduction is needed on the tooth's front side, where the veneer is bonded. No trimming is needed on the backside. With some veneering techniques no tooth reduction is needed at all.)
This is a very important feature of veneers. It means that, as compared to crowns, when they are place less healthy tooth structure is sacrificed. Additionally, the preparation process is less traumatic for the tooth (and possibly the patient too).
Comparing characteristics and applications of crowns vs. veneers.
Crowns and veneers have their own individual set of characteristics that generally make one or the other more suitable for certain applications. Here are some of the factors dentists take into consideration when determining which one makes the better choice for a patient's case.
As you'll see in the next list, in comparison to crowns, which can be used to rebuild and strengthen teeth, porcelain veneers are used in applications that are typically just cosmetic in nature.
- Can be used to produce a color change for a tooth. Slight to moderate changes usually give the most life-like results.
- Can create minor shape changes for a tooth.
- Are placed on teeth whose underlying tooth structure is generally healthy and intact.
- Are strong but brittle. Porcelain veneers typically do best in those situations where the forces placed upon them are relatively light or passive.
- Require much less tooth trimming than dental crowns. Some veneering situations may require no tooth reduction at all.
- In some special instances, porcelain veneer placement may be reversible. In most cases, however, once a veneer has been placed, the tooth will always require some type of covering. This might be another porcelain or other type of veneer, or else the tooth could be further reduced and a dental crown placed.