Crowns

A crown, sometimes called a ‘cap’, is a shell-like restoration that’s cemented to a tooth to restore its shape, function and looks. The shell can be made of a number of different materials, including ceramic, porcelainmetal and gold. (Note that some people call bonding a ‘cap’, but this is a totally different procedure.)

Crowns are used for two main purposes:

  • to replace lost tooth structure and support any remaining structure where there has been extensive decay, erosion, a developmental defect, fracture or trauma
  • for aesthetics

Before a crown can be placed, the foundation of the tooth needs to be made secure. First, any existing fillings are removed and the tooth is checked to make sure there is no underlying decay. A new core or a new foundation may be needed. The outer layer of tooth is then cut back, a mold is taken and a temporary crown is placed. The mold is then sent to the laboratory, where the crown is constructed. This usually takes two to three weeks. We use an alloy with a high gold content to maximise accuracy of the crown placement and minimise allergic reactions. It is paramount that the crown margins are extremely accurate as infiltration of food and bacteria may occur if the crown margins are not well sealed.

Once constructed, the permanent crown is tried in the mouth and the fit, bite and look are carefully checked to make sure they match the existing teeth. Any necessary adjustments are made, then the crown is cemented on.

Crowns generally last between ten and fifteen years, depending on how well they’re looked after.