What is a crown? 
 
A crown is a cap which is placed over a tooth and held in place by dental adhesive or cement.

Crowns are used for several reasons

• As a protective cover for badly decayed teeth or fractured teeth
• As a permanent restoration for teeth with large fillings
• To correct minor problems in natural teeth like spacing and irregular shape or severe discoloration.

Discoloured tooth before treatment

Discoloured tooth after treatment

 
What are crowns made of? 
 
Crowns can be made of a variety of materials.  They can be made of plastic, ceramic or metal alloys.  A combination of metal and ceramic is also possible to maximize strength and simulate the appearance of natural teeth. 
 
How are crowns made? 
 
Firstly, a thorough clinical examination is conducted with radiographs by the dentist.  The suitability for crowns is assessed and any preparatory work is carried out.  Your dentist will also be able to advise on material choices, treatment sequence and any other concerns you may have.

At the second appointment, the teeth to be crowned are prepared. This involves reduction of the tooth size (usually under local anaesthesia) followed by an impression or mould of the prepared tooth.  This trimming of the tooth is required to create space for the crown to be fitted.  The mould taken is then sent to a laboratory where skilled technicians will fabricate the crown. In the meanwhile, a temporary crown is made and fitted onto the trimmed tooth.

At the third appointment, the temporary crown is removed and the tooth surfaces cleaned.  The completed crown is tried on the tooth for fit, harmony with the bite and appearance.  Finally the crown is cemented on to the prepared tooth with dental cement.

Prepared tooth ready to be fitted with crown

Tooth with crown fitted on

  
How long do crowns last and how do I care for them? 
 
Crowns are made of inert materials which do not deteriorate over time. However, the underlying tooth is still prone to decay and gum disease.

Ceramic on the surface may chip or fracture. Avoid chewing excessively hard substances like ice or bones. Daily brushing and flossing are essential for maintaining good oral health as well as keeping the crown trouble free. The most vulnerable portion of the crown is the margin or the junction between tooth and crown.

Regular checkups will enable your dentist to detect and problems with your crown and recommend necessary treatment.

What is a bridge? 
 
A bridge is a means of replacing missing teeth using the neighboring teeth as supporting structures. Bridges are usually done by trimming teeth on either side of a missing tooth like in crowns.  The crowns made are joined together by adding a tooth in between.  The resulting structure is called a bridge. Like crowns, they are also fabricated in a laboratory utilizing the same materials and then fitted in the mouth. Maintenance care for bridges is similar to that for crowns.  The focus is on regular flossing, brushing as well as regular checkups. 
 

Prepared teeth ready for bridge fitting

Teeth with bridge fitted on

Can all missing teeth be replaced by bridges? 
 
Bridges can be used to replace a small number of missing teeth if the neighboring teeth are sufficiently strong. The number of missing teeth, condition of the neighboring teeth, condition of the supporting gums and bone are all important factors which need to be assessed by your dentist prior to making a bridge. Your dentist will also be able to advise on alternative methods of replacing missing teeth after a clinical examination.