There are three basic types of crowns:
- Porcelain outer surface with a metal base crown.
- Pure porcelain or composite crown.
- All metal crown, which is usually gold. They all differ in durability, strength, appearance and cost.
When a tooth is fractured, has a large old filling, or is severely damaged by decay, your dentist may recommend the placement of a crown. Crowns strengthen and protect the remaining tooth structure and can improve the appearance of your smile. Types of crowns include the full porcelain crown, the porcelain-fused-to-metal crown (precious & non-precious) and the all-metal crown. Fitting a crown requires at least two visits to the dentist's office. Initially, the Dentist removes decay and shapes the tooth; makes an impression and fits a temporary or transitional crown of plastic or metal. In a subsequent visit, the dentist removes the temporary crown, fits and adjusts the final crown and cements the crown into place.
A single missing tooth can lead to migrations or premature wear by the other teeth, gum problems and poor aesthetics. Moreover, chewing problems can lead to major digestion problems.
There are two major groups of dentures:
- The dental crown: this is intended to replace a single tooth resting on its root. It may consist of metal, precious metal or ceramic.
- The dental bridge: this is intended to replace one or several missing teeth resting on neighbouring teeth.
- The onlay: this is intended to rebuild part of a damaged tooth. This may consist of resin or ceramic. It is glued in place and enables the living root to be saved.
- The dental facet: this is intended to re-establish the aesthetics of the most visible teeth. It is ceramic.
- The partial dental appliance: this is intended to replace several missing teeth. The structure is metal (a stellite appliance, very strong and rustproof) and is fitted with hooks for fixing on the teeth in the mouth. It can be removed and cleaned.
- The complete set or “dentures”: they are intended to replace all the teeth. They consist of resin.