When a tooth is cracked, decayed, or damaged, a tooth may need to be prepared to receive a crown. As well, this gives us the opportunity to change the shape, realign existing tooth positions, and alter the shade of a natural tooth using crowns. Most crowns are made with either porcelain, aluminous porcelain, porcelain fused to metal, zirconia, or gold.
1st Visit: The dentist will take preliminary impressions of the upper and lower arches. Then the tooth will be shaped in such a way that a crown can be easily seated over the tooth. A temporary crown is fabricated chairside and temporarily cemented over the tooth.
2nd Visit: The temporary crown is removed and an impression of your teeth is taken and sent to a lab where they will fabricate your final crown. In certain circumstances, you may be required to visit the lab in order to take a “custom shade” to match your natural teeth closely. The temporary crown is re-cemented into position again while your permanent crown is being made.
3rd Visit: Your temporary crown is removed once again, and the final crown is placed. The fit is verified by taking a radiograph (x-ray). Once the fit is confirmed, then the crown can be permanently cemented onto the tooth with a special adhesive.
A bridge is meant to replace one or more missing teeth. It is fabricated by fusing individual crowns on adjacent teeth surrounding the space. Bridges can also be used to improve the appearance and shape of individual teeth.
We can also use precious metals such as gold in the fabrication of crowns. Gold is an extremely durable material and has the least reactivity of all types of metals used in the mouth. It is extremely gentle on the opposing dentition and is well-suited on molars in patients who habitually clench or grind their teeth.
Full porcelain restorations have been considered the most lifelike and natural looking restorations available today. Porcelain is not a conductor of heat and cold very efficiently, so sensitivity to hot and cold is not an issue. However, porcelain can also be brittle and fracture easily when it is too thin or it is habitually flexed through the forces of clenching and grinding. Full porcelain crowns are also somewhat weaker because they lack the metal framework present in a porcelain fused to metal or gold crowns.
In order to safeguard against fractures related to thinness, a full porcelain crown must be thicker all the way around than a gold restoration. Therefore, more tooth structure may need to be removed to allow for more bulk of porcelain to improve overall strength and durability.
These crowns have a life-like and therefore are used in areas of the mouth where aesthetics are important. This material is very durable and fracture resistant.
A porcelain fused to metal crown is made by layering porcelain on top of a metal alloy base. It is a combination of metal and porcelain offering the advantages of both stability of the metal base coupled with the aesthetics of an outer porcelain shell.
Zirconia crowns are a popular choice due to their durability, strength and translucent life-like appearance. They last longer than all-porcelain crowns but do not possess similar aesthetics.