Centre Dental

Crowns & Bridges

A crown is a lab fabricated tooth-shaped cap that goes over a prepared tooth.  Once cemented in place, it fully encases the visible portion of a tooth.  It restores a damaged tooth to its original size, strength, shape, and functionality.  It can even enhance the appearance and color of a tooth. 

When do I need a Crown?

• Chipped or fractured tooth
• Tooth with large fillings
• Root canal treated tooth
• Severely discolored tooth
• Crooked tooth or mis-shaped tooth 
• Worn tooth
• A crown is also needed to restore implant and to anchor a bridge.

What Material Choices do I have?

• All porcelain:  great esthetics.
• Zirconium:  strong and natural looking
• PFM (porcelain-fused-to metal):  traditional crown material.
• All metal:  strong, but not esthetic.

What does it involve to get a Crown?

1. Tooth preparation: all broken tooth has to be built by core material (called core buildup), a root canal treated tooth also need a post and core to fill all empty spaces inside a tooth.  The tooth then will be reshaped and shortened to receive a future crown.
2. Impression of the prepared tooth: we use either traditional impression material or iTero digital impression scanner to replicate you teeth in your mouth.  If you are a gagger or impression-phobic, we will use the digital impression system. 
3. Color selection (shade matching) and choosing a crown material.
4. Temporary crown:  we will make a temporary crown to cover the prepared tooth.
5. Crown fabrication: using the impression information (or digital data), a ceramist in our preferred lab makes your custom crown to look like a real tooth.  This may take up to two weeks.
6.  Final crown: the final crown will be tried in your mouth, and if looks good and functions well, we will use a strong cement to glue it to your tooth to complete your crown treatment.  If you don’t tell, your friend may not know which tooth you have just received a crown.

Types of Bridges:

1. Conventional fixed bridges:  teeth on both sides of the missing tooth must be trimmed.  A porcelain crown is then placed on top of each tooth.  A false tooth (pontic) fused (connected) with the two crowns to form a bridge between teeth.
   
    
2. Maryland bridge: a false tooth (pontic) is made two wings, which are glued onto the inner surfaces of the adjacent teeth. It requires two visits to finish. It is commonly used to replace one front tooth.  Due to esthetic limitation, it is used mostly as provisional restoration while waiting for more definitive treatment (such as implants).
   
    
3. Ribbond bridge: a false tooth (pontic) is connected to a ribbon which is glued onto the inner surfaces of adjacent teeth.  Like Maryland bridge, it does not require trimming of the adjacent teeth. Due to limited strength and esthetics, it is used mostly as provisional restoration while waiting for more definitive treatment.  The major advantage of a ribbon bridge is that it can be done chair side in one visit to dentist.  It provide instant esthetic remedy for unexpected tooth loss.
4. Cantilever bridge: a false tooth (pontic) is connected to one end of the adjacent crown.  It mostly used when there are two or more adjacent teeth on one side of the missing tooth with splinted crowns, but a crown on the other side of the missing tooth is not available or impractical to receive a crown.  Cantilever bridge is not recommended for most patients due to its longevity issues.
   
    

Dental Bridge: Pros and Cons

• When a tooth is missing, two adjacent teeth are shaved down to anchor a fake tooth (pontic) making it into a 3-unit-bridge.  If more teeth are missing, a longer bridge is made. 
• It feels and looks natural.  It may last long if you can clean them adequately.
• It can be done in two weeks or sooner.
• However, many patients are unable to clean underneath the bridge resulting decays of anchoring teeth or gum disease.  Eventually, more teeth are lost.
• When one tooth is missing, it is more conservative to place  it by dental implant so that the adjacent teeth can be spared.
• Dental bridge may be indicated if a patient has severe medical condition that a dental implant is not an option.  Also if the adjacent teeth are damaged and crowns are needed to restore them, they can be used to anchor a fake tooth.

If you are not sure what the best treatment option is for your specific condition, please ask Dr Shi and Dr Yeung.  We offer free online and in-office consultation.