Crowns, often called “caps,” cover teeth to restore them to their appropriate shape and size after large fillings, fractures, and/or weakening forces such as intense grinding. In all of these cases, crowns not only cover teeth but provide added support as well. Crowns can also be used to attach bridges, cover dental implants, restore seriously discolored or misshapen teeth, and even as a preventive measure to protect a tooth in danger of breaking. Crowns can be made of all-porcelain (ceramic) material, porcelain fused to metal (for added strength), gold alloys (high noble), or base metal alloys (non-noble). Each of these restorative materials has its advantages and disadvantages. All-porcelain restorations most closely mimic natural tooth appearance. Their strength depends on adequate porcelain thickness, thus this material requires more extensive preparation. Porcelain fused to metal alloy restorations are tooth-colored and stronger than all-porcelain crowns. Gold alloy crowns are very strong and wear resistant. They are well tolerated in terms of biocompatibility, but metal colors do not match natural teeth. Base metal alloy crowns are similar to gold for strength and durability. However, allergy to the non-noble base metals may be an issue with some patients.
Crowns can be placed in as few as two appointments. For porcelain crowns, properly matching the aesthetics of teeth can take more visits but the natural looking cosmetic results are worth it to most patients. Crowns in general are very strong restorations, and they help to protect teeth. If a crown is placed before the tooth is so badly decayed or so weak that it fractures, the necessity of a root canal can often be preempted. This can also help prevent a broken tooth from becoming so bad that it needs to be removed, which would require a bridge or implant for restoration.
In light of their excellent restorative capabilities, crowns have few disadvantages. As they are more extensive restorations than fillings, their relative cost is higher. However, if our doctors recommend a crown it is because we want to help you keep your teeth healthy and looking good for years to come. The problems crowns help to prevent and repair offset the cost.
Also, while crowns are highly resistant, due to normal wear they will eventually need to be re-cemented or replaced. Six to nine percent of teeth that are damaged enough to need a crown may someday need a root canal.