A crown is a restoration made by a technician in a dental laboratory. They can be made of metal, porcelain bonded to metal or porcelain only. Teeth that have had a root canal treatment done or that have lost a lot of substance generally need to be crowned. The format is the same as that for an onlay. It requires 2 visits. At first visit the tooth is shaped and an impression is taken. The patient will wear a temporary crown until the second visit which is generally 2 weeks later. At he final appointment the temporaray crown is gently removed and replaced with the permanent crown and bonded with a very strong bond. Some temporary sensitivity from the tooth for a few days after either of the sessions could occur.
Bridges are a way to replace a missing tooth or teeth and an alternative to implants. A bridge is a fixed dental restoration used to replace one or more missing teeth by joining an artificial tooth to an adjacent natural tooth or implant. The bridge spans the space where the teeth are missing.