Sometimes, when a tooth is very heavily restored, its multiple fillings may not look good or last long because even the strongest filling materials have their limitations. The most durable solution for restoring badly damaged teeth is to prepare the tooth for a crown. The crown not only protects remaining tooth structure, but also restores the original appearance of the tooth. In cosmetic dentistry, crowning is also a technique to straighten teeth. Cosmetic crowns are often full ceramic restorations.
Examples of ceramics that are very natural-looking and without metal backing are included in our smile gallery before/after section. Unlike fillings, crowns cannot be constructed in one visit. The dentist must first take impressions of your mouth to make some study models and also to construct temporary crowns, usually made of resin. Study models help the dentist plan the case. Every tooth is unique and will require the dentist to exercise judgement on where to trim the tooth and how much to trim. For cosmetic cases where tooth positions are changed by crowning, the dentist may have to discuss his plans with the patient before proceeding to the preparation stage.
Teeth which are still vital will feel sensitive when trimmed, so a local anaesthetic is usually given. This is to make space for the crown and adequate clearance is absolutely necessary. The thicker the crown, the stronger it is. Once the preparation is complete, the dentist takes an impression of the prepared teeth with a rubbery material. The final crowns will be fabricated on this impression. At the end of the crown preparation visit, temporary crowns are cemented to protect the remaining tooth structure.
When the permanent crown is completed in the laboratory (usually takes about a week), the temporary cowns are removed from the mouth to be replaced by the porcelain crown which is then permanently cemented over the prepared tooth. The crowning process is thus completed. Crowns can be very simple or complex, depending on the condition of the mouth and the needs of the patient. Mobile teeth are not suitable for crowning. Teeth with bleeding gums will also affect the accuracy of the impression. For cosmetic realignment, a considerable amount of skill and experience are required.