Porcelain Fused to Metal Crowns

Reasons to Crown a Tooth

Crowns are fitted over the teeth for a number of reasons. Crowns can restore the regular functions of a tooth, like biting and chewing, and can also be fitted for cosmetic reasons, improving the form and appearance of the tooth. A bridge spans space where one or more teeth have been lost. The teeth on either side of the space are crowned.

Just like the hard bones of the body, teeth can crack and break. The cusps, or raised areas of molars can break and chip with regular chewing and biting motions. These fractures create vulnerabilities within the tooth and must be protected from oral bacteria that can lead to decay and infection. A tooth may be weak for other reasons, and crowns can provide a strong outer covering that is superior the natural composition of the tooth. In some cases, a broken tooth may be worn or missing much of its regular size and shape, and can benefit from being crowned.

Today, we have many options for materials to crown a tooth. Each of these materials has some advantages and disadvantages. We will be happy to help you choose the best material that fits your needs.

Porcelain Fused to Metal Crowns

Porcelain-fused-to-metal (PFM) reconstructions have been used widely in dentistry until today. PFM restorations have a metal shell on which porcelain is fused in a special high temperature oven.

Creating the same natural look with PFM crowns is far more difficult because we must disguise the gray metal substructure beneath the porcelain. Since a layer of very opaque porcelain must be used to mask the metal, the space used for that layer minimizes how thick the outermost translucent layer of porcelain can be. However, a natural appearance can be achieved with PFM crowns if more of the natural tooth structure can be reduced.

Another common aesthetic concern with PFM crowns is the dark line that is sometimes seen near the gumline. This dark line occurs if the gums begin to recede or if the tissue hugging the neck of the tooth is thin and translucent. In general, all-porcelain crowns are the best option for restoring teeth in the smile zone. On the other hand, PFM crowns or porcelain fused Zirkonia(PFZ) crowns or monolithic Zirkonia crowns are, generally, ideal for posterior teeth.