FIXED PARTIAL DENTURES (FPD)

A Fixed Partial Denture, also known as a "Bridge" is a restoration that replaces one or more missing teeth and is cemented to your natural teeth (Fig. 4).  It "bridges" a space, from one tooth to another on either side of the space (Fig. 1).  Before the advent of dental implants, it was considered the best method of replacing a single missing tooth. FPDs can be made of all gold, all porcelain, or a combination of porcelain and gold. 

 

Fig. 1     Single missing tooth, bounded by two healthy teeth.	Fig. 2     The teeth next to the missing tooth are reduced.  The amount of tooth removed depends on the materials used to make the bridge.      An impression is taken and sent to the lab to fabricate the bridge.

ADVANTAGES

1.  Keeping teeth will help preserve the bone in the vicinity of the teeth.  This will provide a better
     foundation and a more secure prosthesis.
2.  A FPD looks like teeth, feels like teeth and chews like teeth.
3.  You can bite harder with a tooth supported FPD than with a removable partial denture (RPD).  With a
     tooth supported bridge, you are chewing on teeth. With a removable partial denture, you are
     chewing on teeth and the gum.  The gum cannot take as much pressure as the teeth.
4.  Unlike a partial denture, the gum under the bridge will not get sore, because the biting pressure is 
     on the support teeth (abutment teeth) and not on the gum.
5.  A bridge is much smaller than a partial denture. 
6.  A bridge  replaces only the missing teeth...no plastic base, no wire hooks (Fig. 4). 
7.  A well made bridge can appear very natural and esthetic.

Fig. 3    After the bridge is returned from the lab, it is tried in the mouth.  The fit and bite are adjusted as needed.	Fig. 4     After the prosthodontist and the patient are pleased with the result, the bridge is cemented to the natural teeth.

 

DISADVANTAGES

1.  Depending on the number of teeth replaced, bridgework (FPD) may be more expensive than
     a removable partial denture (RPD).
2.  The teeth next to the empty space will need to be prepared (Fig. 2) for the crowns (bridge retainers)
     supporting the FPD.
3.  The teeth supporting the FPD (abutment teeth) can still get cavities and gum disease.
4.  90% of all three unit bridges (tooth-space-tooth) are replaced after 12 years.
5.  If an abutment tooth is lost due to decay, trauma or gum disease the FPD will fail.
6.  Long span bridgework (more than 3 or 4 teeth) is more prone to problems.
7.  The longer the bridge, the more expensive it is to remake.
8.  If an abutment tooth is lost because or decay or fracture, then the next bridge will be even longer, or
     may not be possible at all.
9.  10-15% of all teeth that are crowned for bridge work will require a root canal.
10. If a  root canal is required after the bridge is cemented, it may weaken the supporting tooth and    
      cause the  bridge to fail.
11. Oral hygiene is more difficult.  It is necessary to thread dental floss under the bridge to clean the
      underside of the artificial replacement tooth (pontic).
12. Gum recession due to aging or disease may expose the margin of the crown at the gumline.  This
      may create an unesthetic display of tooth root or metal.
13. If gold is used on the chewing surface of the bridge, it may be visible when talking or smiling.
14. If porcelain is used to make the FPD, it may crack or break, especially in "long span" bridges of more
      than 4 teeth.  The chipping and breaking of porcelain may also be a problem if you clench or grind
      your teeth (bruxism), a common problem for many adults.
15. Overtime, the natural teeth next to a porcelain bridge will naturally get darker as the teeth age. 
      This will cause a mismatch in shade. Simple bleaching of the teeth may solve this problem.
16. Porcelain cannot be bleached like natural teeth
17. If decay gets under a crown supporting the FPD, it may be necessary to remove the bridge and
     make a new one.