A bridge is a prosthetic tooth fixed to one or both (usually both) adjacent teeth and is not removed. The conventional bridge uses a crown-type structure on the supporting teeth with the prosthetic tooth attached to the side. The bridge may be made of porcelain-metal, or metal-free zirconia (a high strength white mineral)
Conventional bridges tend to be used to replace back teeth, where the biting forces are relatively high, needing a strong bridge structure. They can also be used to replace a missing tooth where the adjacent tooth or teeth are filled or crowned. However, the supporting teeth must be healthy with no sign of infection. Root canal filled teeth are rarely strong enough.
At the first appointment, it is usually necessary to numb the area with a local anaesthetic before the procedure. The supporting teeth either side of the missing tooth are shaved down by around 1mm around the circumference and from the biting surface, leaving the cores of the teeth intact. Impressions will be taken to allow the dental technician to construct the bridge. A temporary bridge (or sometimes single crowns on the supporting teeth) will be fitted. At the second appointment, the temporary bridge or crowns will be removed, the bridge will be tried in to check its fit and appearance, and it will be cemented in place.
A conventional bridge will last an average of 10-12 years. This is not a minimum – 50% will fail before this time. Bridges may fail by debonding, by the supporting teeth developing decay or abscesses, or by the supporting teeth fracturing inside the bridge. In some cases, the bridge can be refitted or remade. In others, the supporting teeth may be irreparably damaged and may need to be removed.
|Strongly fixed in place||Healthy enamel must be shaved off supporting teeth|
|Good aesthetics||Supporting teeth are at increased risk of decay and abscesses|
|Supporting teeth may be irreparably damaged if bridge fails|
|Jawbone underneath bridge will shrink away|