Crowns are restorations that replace the entire visible structure of a severely damaged tooth. A bridge is a replacement tooth anchored by crowns or existing teeth on either side.
What is a crown?
Sometimes the surface of a tooth becomes too badly damaged to be fixed with a filling or other dental technique, but the root structure beneath the gums is still strong. In this case, we can cement a crown or “cap” on the old tooth. This crown will completely cover what is left of the existing tooth, and will be sized and shaped just like the original healthy tooth. Crowns are made of different materials, and the circumstances of each patient will determine which material is best.
All Porcelain or All Ceramic Crowns
These crowns offer the advantage of a very natural appearance, and for this reason are often used for front teeth. Porcelain can be created to perfectly match your surrounding teeth, making the crowns almost indistinguishable. This type of crown does require considerable preparation, leaving less of the existing tooth, and it is often challenging for the dentist to get a fit as tight as with a gold crown. Their beautiful, life-like appearance continues to make them a popular choice.
This popular crown type provides an excellent combination of aesthetics and durability. The porcelain is color matched to your existing teeth and fused to a metal base. With a metal center, this type of crown can never match the translucency of a natural tooth or an all porcelain crown, and a thin darker line can develop where it meets the gum. However porcelain-over-metal crowns look very natural and are exceptionally strong and durable.
Gold is an excellent material for crowns because the material is extremely workable and provides an excellent fit between the crown and the existing tooth. Gold requires the least preparation of the existing tooth, keeping more of the original tooth structure than is possible with other methods. There is no possibility of gold crowns chipping, and since they are not as hard as porcelain crowns, they are not as likely to cause wear on other teeth. The downside of gold may be its distinctive appearance. In the back of the mouth, where gold is often used, this may not be an issue. However, when it is visible in your smile, the gold crown will make an obvious contrast with natural teeth.
How long do crowns last?
Crowns are considered permanent dental restorations. With proper hygiene a dental crown will probably last from ten to fifteen years, but could last much longer.
When a tooth is missing, and not just damaged, crowns can be used as anchors on adjacent teeth, with a false tooth attached to “bridge” the gap. For more information on bridges, click here.