Crowns are used to repair and protect damaged or weak teeth. A crown will often be recommended where the damage is too extensive to be repaired by a simple filling or inlay. The weak or damaged part of the tooth is carefully removed and covered with the 'crown' which is bonded to the remaining tooth. The end result is both strong and durable.
Crowns can be made of metal, but all-metal crowns are normally only fitted to back teeth. Where a crown is required for front teeth, the metal is covered with porcelain for a more natural look. For a completely natural look, with the end result being virtually indistinguishable from a real tooth, the crown can be hand-made, wholly from porcelain.
Crowns can also be used to improve the appearance of mis-shapen or discoloured teeth.
Preparation time will vary depending on the condition of the damaged tooth. The tooth will be reshaped, to ensure that once the crown is fitted, it remains the same size and shape as the natural teeth. It may also need to be built up with a filling first. A local anaesthetic is usually given prior to preparation, to avoid any discomfort.
After preparation, an impression is taken of the tooth to be crowned and nearby teeth, using a soft mouldable material. This impression is given to a dental technician, who uses it to build your crown to the exact size and shape required. This will ensure that the crown fits comfortably. When using porcelain crowns, the colour will also be matched to the natural teeth.
Whilst the crown is being made, a temporary crown will be fitted. This will not be as strong as the final crown, but can still be chewed upon.
Once the crown is ready, it will be tried in place and small adjustments made to ensure a comfortable bite is maintained. Once you and your dentist are happy, the crown is glued in place. Crowns are sometimes held in place with a small peg in your root canal, if there is a lot of the original tooth missing.
The crown can last for many years if good oral hygiene is maintained, depending on the condition of the original tooth. Additional care should be taken to keep the crown and surrounding area clean. Your dentist or dental hygienist will recommend an appropriate home care regime.
Crowns fall within an area of dentistry known as Prosthodontics.