Dental Crown

What is a dental crown?

A dental crown is used to replace significant parts of your tooth that are missing. This can be due to dental decay, disease, an accident or perhaps the tooth was like that from birth. A dental crown will cover the entire underlying tooth, it will touch the opposing teeth and adjacent teeth. A dental crown can be made for a front tooth or back tooth.

The dental Crown procedure

A crown involves the removal of tooth structure to turn the tooth in to stump, over the top of this a crown or cap is made. If your tooth is badly broken down to start off with, cutting it down like this can be beneficial as the crown can restore the tooth strength and remove the decay.

The procedure generally involves:

1. Initial consultation and discussion about the suitability of a dental crown.
2. Preparation appointment
   1. A local anaesthetic will be provided.
   2. The underlying tooth is trimmed down to accept the dental crown.
   3. An impression of the trimmed down tooth is taken and sent to the dental laboratory.
   4. A temporary crown is fitted.
3. The crown will then be made by a dental laboratory, this takes approximately 2 weeks.
4. Fitting appointment.
   1. A local anaesthetic will be provided.
   2. The temporary crown is removed.
   3. The permanent crown is tried in.
   4. If you are happy with the permanent crown it will then be permanently bonded to your tooth.
5. Follow-up appointment to ensure everything is okay.

However, if the tooth is otherwise healthy trimming the tooth down to a stump could be considered a destructive way of restoring that tooth and perhaps a dental veneer would be preferred.

What are dental crowns made from?

A crown is a permanent new covering for the visible section of your tooth. They are normally made from 3 different materials.

• All porcelain or tooth coloured crowns
• Metal crowns
• A combination of metal and tooth coloured material

All porcelain or tooth coloured crowns

These are often made from either Zirconia (the same material that is used in hip replacements an formula one engines… very strong in other words!) or a ceramic material – e.max crowns are very popular today.

These crowns have the tendency to be much more aesthetic than any other crown as they let the light shine through and are not opaque, however until recently they were not as strong as other types of crown and were therefore more prone to fracture.

Metal crowns

These are still widely regarded as the best crown from a dental point of view, especially when made from Gold. Gold crowns have been made for many years and their success is now well documented. They are very strong and gold is exceptionally kind to your surrounding teeth – however many people nowadays simply don’t like the look of gold crowns.

A combination of metal and tooth coloured material

Often called a PFM (Porcelain Fused to Metal) this type of crown has it’s history back in the 1960s when it was first discovered that dental ceramic could be bonded to metal. These crowns are very strong, very aesthetic and have a long history of success in dentistry.

They are being used less and less as they are not quite as aesthetic as a metal free crown because the light is not able to travel through them, this has the tendency to make them look brighter and more opaque.

How are crowns made?

A variety of techniques are used to make crowns, from traditional ‘lost wax’ techniques to the ultra modern CADCAM crowns.

CADCAM or Computer Assisted Design Computer Assisted Manufacture is a growing industry within dentistry and many systems such as:

1. CEREC by Sirona
2. iTero by Straumann
3. Lava by 3M Espa
4. Nobelbiocare