Dental crowns: is CEREC the best option?
A dental crown is a covering that goes completely around a tooth. They can be made from various materials but usually from pure porcelain that is fused to a metal substructure, often gold or from porcelain only. Over the last 10 years, we have implemented the latest in German engineering technologies in dentistry, which allows us to digitally create your dental crown in one visit. See our CEREC section below for more information and videos.
Crowns are used to support a tooth and decrease the tooth’s chances of fracturing. They are especially useful when a tooth has been heavily filled or root-filled and the remaining tooth is weak or there is not enough tooth structure left to hold in a filling. Crowns are also used for aesthetic reasons when we need to change the shape or colour of a tooth.
What does the procedure involve?
The length of time it takes to prepare a tooth for a crown depends on the difficulty of the situation. Usually a minimum of 1 hour is required in the dental chair. An impression (mould) is taken of the prepared tooth and sent to a dental technician who takes approximately 2 weeks to construct the crown. A temporary crown is made of plastic and is placed on the tooth for this time, so that you can eat properly and the tooth looks normal. It takes approximately 30 minutes to cement in the new crown on the next visit.
How long will a crown last?
Generally a crown fails not because there is something wrong with the crown, but due to decay in the tooth around the crown, or a change in the rest of the mouth (such as teeth get darker, but crown stays the same) and this makes the crown stand out or the gum recede around the crown.
Depending on the situation, a crown should last for approximately 10 years, if the supporting tooth stays healthy. It is important though that you maintain regular dental check-ups over this time, because if something starts going wrong with the crown it can more easily be corrected at an early stage.
What are crowns made of?
Two major types of alloys are now available, as well as pure porcelain.
High noble metal crowns are mostly gold, but can be palladium, silver, occasionally platinum, zinc, copper. Gold alloys have been used for many years for the construction of crowns or fixed bridges. They provide excellent, strong, long-lasting service. Base metal crowns are mostly nickel, but chrome or cobalt can also be used.
All of the above metals are used either as the sole constituent of a crown, or as a base on which porcelain is fired (baked). Most people have no biologic response to the base metals. If you have known allergies to metals, please tell us. We usually use high-noble metals. The cost of these is somewhat higher than base metals.
Porcelain only crowns
Pure porcelain crowns are now being used more extensively.
CEREC dental crowns in a single visit
CEREC restoration is one of the latest ways to construct a crown or veneer.
What is CEREC technology?
It is an automated process that creates crowns and veneers in an efficient, accurate and painless way, more effectively than other procedures that have come before it. Using 3D imaging and special software, the exact dimensions of a patient’s teeth are calculated and a digital scan of the required crown is created.
A high precision cutting and tooling machine then sculpts a tooth to create an exact replica of the scan. The crown is then ready for immediate application to the tooth. The whole process can be done in a single visit to the dentist.
CEREC crowns vs traditional dental crowns
Traditionally veneers and crowns required two time-consuming dental visits. The first visit was to take a mould of the required crown and a second visit to apply it. In between that time a temporary filling may have been needed as well. Using CEREC technology, your crown can be designed, milled and fitted in a single visit, compared to almost a week using the traditional method.
Because CEREC technology is digital, it removes the need for moulds, which is great relief for those patients who gag. It also reduces the need for anaesthetics (numbing) to a single visit. The traditional method is still used in certain cases, such as bridges. Research has also shown that a CEREC crown is just as strong and durable as a normal one. And the aesthetics are excellent.
Take a look at this video to see how CEREC works: