Crowns and Bridges


Crowns

What Are Crowns?

Crowns are the ideal restoration for teeth which have been broken or weakened by decay or very large fillings. The crown fits over the remaining part of the tooth, making it strong and giving it the shape and contour of a natural tooth. Crowns are sometimes also known as 'caps' and can be made from porcelain, gold or a combination of these two materials


Why might I need a crown?

There are a number of reasons, for instance:
  • The tooth may have been weakened by having a very large filling.
  • You may have discoloured fillings and would like to improve the appearance of the tooth.
  • You may have had a root filling which will require a crown to protect it.
  • You may have had an accident and damaged the tooth.
  • It may be required to hold a bridge or denture firmly in place.


What Are Crowns Made Of?

Crowns are made of a variety of materials, and new materials are continually being introduced. Here are some of the options available at present:
  • Porcelain bonded to precious metal: This is what the majority of crowns are made from. A precious metal base is made and porcelain is then applied in layers over it.
  • Porcelain: These crowns can look very natural and are most often used for front teeth, especially for younger people. Traditionally, this type of crown is not as strong as the porcelain fused to metal type of crown but offers superior aesthetics
  • Precious metal (gold and palladium): These crowns are very strong and hard wearing but are usually used at the back of the mouth where they are not visible and have been superceeded to a large extent by more aesthetic alternatives
  • Zirconia Porcelain Crowns (e.g. Lava, Procera): These porcelain crowns offer the best of both worlds, combining high strength and unrivalled aesthetics and are suitable for all areas of the mouth
 

How is a crown made?

Firstly, the tooth is prepared to the ideal shape for the crown with the amount of the tooth removed matching the thickness of the crown to be fitted. Once the tooth is shaped an impression is taken of the prepared tooth and of the opposing jaw which are then sent to the dental laboratory for the crown to be made. A temporary crown is fitted to restore aesthetics, function and comfort whilst the crown is being made.
At the second appointment, the temporary crown is removed, the tooth cleaned and the permanent crown tried on to check fit, function and aesthetics. Finally the crown is then fitted using a special dental adhesive.


Who makes The Crown?

The impression and shade information will be given to a Dental Technician who is skilled in making crowns. In our practice, our private crowns are made by a bespoke dental laboratory specialising in producing some of the finest quality crowns, bridge and implant restorations in the country.


Will The Crown Be Noticeable?

No. The crown will be made to match your other teeth as closely as possible. The shade of the neighbouring teeth will be recorded to make sure that the colour looks natural and matches the surrounding teeth. This is done using a shade guide. The technician will then be able to match the characteristics of your own teeth. In some cases, the characterisation is so detailed that the only way to ensure a perfect match is to photograph the adjacent teeth and email this to the laboratory.


How long does the treatment take?

At least two visits are needed, the first for the preparation, impression, shade taking, and fitting the temporary crown; and the second to fit the permanent crown. The first appointment would normally be an hour long.


Does It Hurt To Have A Tooth Prepared For A Crown?

No. A local anaesthetic is used and the preparation should feel no different to that of a filling.


Are Post Crowns Different?

Post crowns may be used when the tooth has been previously root filled or if there is insufficient tooth remaining above the level of the gum. A channel is prepared within the remaining root and a post is constructed to fit into the root canal. This can be prefabricated stainless steel, carbon fibre, or custom made of gold. One end of the post is cemented into the root canal, and the other end holds the crown firmly in place.


Are there Any Alternatives to Post Crowns for Root-Filled Teeth?

If a root-filled tooth is not completely broken down, it may be possible to build it up again using filling materials. This 'core' is then prepared in the same way as a natural tooth and the impressions are taken.


Maintenance

Crowns need to be looked after. The weak point is where the crown meets the tooth and therefore it is vital that you brush and floss thoroughly around your crowns to prevent decay developing at the crown margin.


Bridges

What is a bridge?

A bridge is a laboratory made restoration used to replace 1 or more missing teeth. The teeth adjacent to the gap are crowned and artificial porcelain teeth are attached to these to fill the gap


What are bridges made of?

Bridges usually made of a precious metal base with porcelain fused over the top to provide optimal aesthetics and strength.
More recently, as with crowns, Zirconia based bridges that do not contain any metal have been developed in order to achieve optimal aesthetics whilst having similar strength and durability to metal based designs.
In the front of the mouth, more minimal adhesive type bridges can sometimes be used where a metal backing is bonded to the adjacent tooth which in turn carries the false porcelain tooth.


Who makes The Bridge?

The impression and shade information will be given to a dental technician who is skilled in making bridges. In our practice, our private bridges are made by a bespoke dental laboratory specialising in producing the some of the finest quality crowns, bridge and implant restorations in the country.


Will The Bridge Be Noticeable?

No. The bridge will be made to match your other teeth as closely as possible. The shade of the neighbouring teeth will be recorded to make sure that the colour looks natural and matches the surrounding teeth. This is done using a shade guide. The technician will then be able to match the characteristics of your own teeth. In some cases, the characterisation is so detailed that the only way to ensure a perfect match is to photograph the adjacent teeth and email this to the laboratory.


What’s involved?

As with crowns, the procedure involves two appointments. The first is to prepare the teeth, take an impression, match the shade to the adjacent teeth and fit a temporary bridge. This would normally be carried out under local anaesthetic. The second, shorter appointment is to remove the temporary and fit the permanent bridge


Should every gap be filled with a bridge?

No. Where the bite is stable, where there are sufficient teeth to function and chew and where there is no aesthetic need to fill the gap then there may be no need to have a bridge. However, as well as being aesthetically undesirable, a gap left by missing tooth can put greater strain on the teeth at either side. Your 'bite' can also be affected because the teeth next to the space can tilt, drift or over erupt into the gap and alter the way the upper and lower teeth bite together. This can then lead to food getting packed into the gap, causing tooth decay or gum disease.


What are the advantages of a bridge over a denture?

There are numerous advantages:
  • A bridge is fixed permanently in place
  • It feels like having your natural teeth back
  • It doesn’t cover the palate or interfere with the tongue space
  • Speech and chewing is normally unaffected
  

Maintenance

As with crowns you will need to clean thoroughly around and underneath your bridge every day, to prevent problems such as decay and gum disease which can lead to bridge failure. Your dentist will show you how to do this at the fit visit using special floss (Superfloss) and a normal toothbrush as conventional floss cannot clean the critical areas.