A crown is an artificial restoration that fits over the remaining part of a prepared tooth, making it strong and giving it the shape of a natural tooth.
A crown is sometimes known as a 'cap'. Crowns are an ideal restoration for teeth that have been broken, or have been weakened by decay or a very large filling. They can be made of porcelain or gold or a combination of these materials.
A dental crown could be used for a number of other reasons, for instance:
• you may have discoloured fillings and would like to improve the appearance of the tooth
• you may have had a root filling which will need a crown to protect it
• it may help hold a bridge or denture firmly in place.
A dental bridge is usually used where there are fewer teeth to replace, or when the missing teeth are only on one side of the mouth. Bridges are usually made of a precious metal base.
If the bridge will show, porcelain is then bonded to the base. Sometimes, there are other non-precious metals used in the base to reduce the cost.
You should replace missing teeth for a number of reasons. Your appearance is one reason. Another is that the gap left by a missing tooth can mean greater strain is put on the teeth at either side.