Central Dentists Springfield LakesDr. Safa Souzani & Associates

Unit 6/31 Springfield Lakes blvd.Springfield Lakes Qld 4300

Tel: 07 3381 8888

A crown or "cap" is a covering for the top portion of the tooth. It looks and functions like a natural tooth. The crown is cemented on to the remaining tooth structure and is therefore referred to as a "fixed" non removable restoration. The purpose of a crown is to hold the remaining tooth structure together, helping to prevent further destruction of tooth and in some cases repairing teeth that are otherwise non repairable.

What are indications for a crown? • Large fillings involving half to three

quarters the tooth or more, resulting in a weakened tooth increasing likelihood for fracture.

• Endodontic therapy (root canal treatment), this weakens the tooth increasing likelihood of fracture, this is especially true for posterior teeth (premolars and molars).

• Cracked teeth in which the crack is deep enough and in a direction, which can lead to pulpal death or tooth loss.

• To improve the contours and appearance of existing teeth.

• Teeth that are unfillable with little or no tooth structure to hold a filling above the gum line.

• To correct the occlusal plane (chewing surface alignment).

What is the procedure for a crown? The process consists of two appointments.

The first appointment is to prepare the crown, and generally takes 1 to 1-1/2 hours to complete. This appointment requires anesthesia. The tooth is carefully reduced to give adequate reduction for the crown (cap). Reduction amounts vary depending on the type of crown and materials to be used. Next an impression of the reduced tooth is made, a bite registration is taken, tooth shade is selected and last a temporary crown is fabricated and cemented to the tooth for function, protection and to preserve the tooth's location.

The second appointment is to try in and cement the permanent crown. Anesthesia is generally not required, and is preferably not used to facilitate patient feed back about how the bite feels. This appointment generally is scheduled for 45 minutes.

The Cost of a Dental Crown ranges from $1000 to $1400.

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Dental Crowns/Bridges

Central Dentists Springfield LakesDr. Safa Souzani & Associates

Unit 6/31 Springfield Lakes blvd.Springfield Lakes Qld 4300

Tel: 07 3381 8888

What are crowns made of?

Today's dental materials are remarkable and have lead to many different materials for today's crown and bridge work.

• Gold crown: generally this is cast from yellow gold but can be silver in colour depending on the alloys properties. Gold crowns tend to fit the best and have the best wear characteristics on the opposing teeth much like natural tooth structure.

• Porcelain fused to metal: this is perhaps the most common form, and is used where aesthetics and durability are required. PFM crowns give you good fit and esthetics, the porcelain can be abrasive.

• Porcelain: this crown has no metal substructure and therefore is very esthetic. With today's materials their strength is approaching PFM crowns. Today's porcelain crown materials have improved abrasive properties but tend to be harder then tooth structure.

How long do crowns last? This is a complex question due to the many factors involved. One thing to remember is that crowns are a mechanical device and will need replacement at some time. Here are some factors when considering the longevity of a crown.

• The amount of tooth structure remaining to retain the crown. The less tooth the worse. This is a consideration when selecting the type of crown, some types of crowns require more tooth reduction/removal then others.

• The oral hygiene of the patient. If a patient has poor oral hygiene the prognosis is poor.

• The oral habits of the patient. Is the patient an ice chewier, nail biter, bruxer (tooth grinder), or clincher.

• The patients skeletal pattern (jaw relationship). Some patients can generate incredible amounts of biting (compressive forces) increasing the likelihood for porcelain fracture.

• The quality of the tooth preparation.

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3 Unit Bridge replacing missing tooth