Crowns

What are Dental Crowns?

A dental crown, a cap for the tooth which is made of porcelain or metal, covers the tooth to improve its shape, size, strength, or to improve its appearance. If left on its own, the tooth usually is at some risk, with considerable damage that needs to be stopped to keep the tooth strong. However, sometimes a healthy tooth needs to be crowned in order to adapt a dental appliance to it for stability. This is the case with partial dental plates and to replace missing single teeth by attaching a replacement tooth to the adjoining teeth. Crowns, when cemented into place, fully encase the entire visible portion of a tooth that lies above the gum line.

Other reasons for using a crowns to restore teeth are

1. To protect a weak or broken tooth from breaking apart
2. To restore an already broken or severely worn tooth
3. To protect the integrity of a tooth with a very large filling
4. To anchor a dental bridge
5. To cover ugly, misshapen or discolored teeth
6. To cover a dental implant

What are crowns made of?

Permanent crowns can be made from either solid components such as metal, resin or ceramic – or they can be made of metal encased in porcelain to closely resemble a natural tooth. The structure of the crown can depend on several factors including visibility, usage, cost, and durability. For instance, a molar which is typically used heavily for chewing, but is not usually visible is a good choice for a metal crown, saving on cost over porcelain a crown.

Porcelain-fused-to-metal dental crowns can be color-matched to your adjacent teeth, but are more vulnerable to chipping and breakage. Still the visual advantage of a indiscernible replacement tooth can be worth the additional cost and potential need for future replacement. Another risk with this type of crown is that sometimes the metal beneath the crown’s porcelain can show as a dark line at the gum line and can become more visible over time if your gums recede. Nonetheless, these crowns can be a good choice for front or back teeth.

All-resin dental crowns are the least expensive of all other crown types. However, they wear down over time and are more prone to fractures than porcelain-fused-to-metal crowns. They are a good temporary choice for someone, such as a child, who has not replaced baby teeth with adult ones.

All-ceramic or all-porcelain dental crowns provide the best possible color match to natural teeth and can be custom colored to the individual. However, they are not as strong as porcelain-fused-to-metal crowns and they can wear on opposing teeth more than either metal or resin crowns. All-ceramic crowns are a good choice for front teeth, because they can hardly be distinguished from the adjacent natural teeth.

Crowns – Temporary versus permanent?

Temporary crowns can be made the same day in your dentist’s office in order to protect your tooth while the permanent crowns are made in a dental laboratory. Although functional, temporary crowns are made from universal “blanks” so the external appeal is lacking compared to the permanent crown which is custom constructed, fit and color corrected for the individual.  Temporary crowns are made of acrylic or stainless steel and can be used as a temporary restoration until the permanent crown can be made by the dental laboratory.

The Clinical Procedure

During the crown procedure, the dentist will prepare the tooth and make a molded impression of the teeth to send to a dental laboratory. A temporary crown is created during this visit to protect the tooth while the final restoration is being made. Once completed, the crown is cemented or bonded during the next appointment.

Fixed Partial Dentures, Dental Implants and Crowns

Fixed partial dentures (aka dental bridges) are an extension of the dental crown treatment for replacement of missing teeth. Crowns are placed on the teeth adjacent to the missing tooth or teeth and connected to a missing tooth-like replica. Fixed partial dentures can serve as a functional and aesthetic restoration. The replacement appliance can also be attached to dental implants. Implants can act as anchors for dentures and partial dentures by attaching a permanent post into the bone under the gum line and then attaching a crown with the proper appliance to hold the denture or partial denture.

The dental crown has become one of the most versatile means of restoring and protecting vulnerable teeth, and often is the last option before having to remove the tooth. If one or more of your teeth are breaking off, heavy decayed or aching, you may need a crown to save the tooth and keep your smile at its brightest.