Crowns & Bridges
Dental Crowns & Bridges
If you have a weak tooth or are missing one or more teeth, you may need a crown or a bridge. A crown sits over a tooth that may have been broken or weakened and serves to return the tooth to its former strength and natural shape. If you are missing one or more teeth, a bridge may be fitted to stop the surrounding teeth from moving out of place and will be anchored by one or more crowns to restore the appearance and function.
Dental caps are exactly the same as crowns and bridges and is the more commonly used term amongst the general public. Dental caps are often spoken about in the media and the press however the official term is a crown or a bridge so you will be unlikely to find any dentist refer to them as caps!
Dental Crowns for Front Teeth
When we make crowns for your front teeth, generally speaking, the appearance is the most important factor. One of the problems that is faced with dental crowns is finding a material that is strong and resilient enough to last in the oral environment with the constant impact and use that your teeth get.
The issue is one of the transmission and reflection of light through the dental Crown. We need to use a material which exhibits the same transmission and reflection of light as a natural tooth does, if we do not then the crown will look different to its surrounding natural teeth.
In years gone past gold alloys were used for dental crowns. The existing tooth was reduced down to a stump, a gold alloy thimble was made over the top and then highly aesthetic dental ceramic was applied to make the Crown look like the natural teeth. This technique is still used extensively today and the results are often excellent.
The problem with this type of porcelain fused to metal Crown is again one of the transmission and reflection of light, clearly light cannot pass through the metal and so it is reflected back. This has the tendency of making the Crown look brighter. It certainly is possible to make this type of Crown look fantastic, however a highly skilled dental technician is always required to work closely with the dentist to ensure that the result is perfect.
In more recent years metal free crowns have become more popular, especially with the advent of materials like zirconia which are used extensively in general surgery in the replacement of hips. Zirconia crowns can often be more expensive to manufacture than porcelain fused a metal crowns and some research shows that they may not be quite as resilient.
However, over all metal free crowns are far better to use in the front teeth area due to their natural light reflecting and transmitting properties which make them similar to natural teeth.
Problems with Dental Crowns
As dental crowns have been in common use since the 1960s they have had a considerable amount of research, testing and trialling and have proved themselves over and over to be an excellent choice to restore a broken down tooth. Dental crowns can be problematic in the following areas:
- Aesthetic problems (the way they look).
- Functional problems (the way they work with your surrounding teeth and jaw).
- Longevity (the length of time they last)
Grey Lines on Dental Crowns, why does this happen?
- Underlying metal showing through, if indeed it is a porcelain fused to metal crown.
- A shadow from the Crown cast over the gum area.
The Procedure for Dental Crowns
The procedure for making a dental Crown would normally be as follows:
- An initial diagnosis is made that you need to have a broken down tooth restored.
- The remaining tooth structure will be reduced to a stump, known as a ‘preparation’. An impression will then be taken of this preparation and sent to the dental laboratory.
- The new dental Crown is then fitted approximately 2 weeks later.