Crowns are often called “caps”. When teeth have been badly damaged by decay with large parts missing, broken or worn excessively, crowns should be routinely made.
A Dental crown helps strengthen the tooth by being a hard outer shell that protects the tooth structure within. The crown in effect becomes the tooth’s new outer surface.
Crowns are routinely made for extensively broken and worn teeth. The crown can restore a fractured tooth, protect weak tooth particles from breaking, restore an implant, hide a discoloured or poorly shaped tooth and help seal a root canal treated tooth. Importantly and most commonly a crown replaces a large filling when there isn’t enough tooth left, protecting the tooth before it breaks.
Crowns are commonly made of all porcelain, metal with porcelain or gold. Today with new technology available we can make crowns to look exactly like your teeth especially if the crown is all porcelain. However, an all porcelain crown is not always possible.
What is involved in making a crown?
The tooth is reduced slightly in size to make room for the crown to cover the tooth. Once the tooth is reduced an impression is taken to send a copy of the tooth to the Laboratory technician who will make the crown.
While the crown is being made in the Lab, a temporary crown is placed over the prepared tooth. Sometimes the Lab technician will need to see the tooth to select the shade for the new crown in order to match it to the rest of the teeth.
When eating with the temporary crown it is important not to eat hard or sticky foods or you may knock it loose. If the temporary comes loose it is important that it is recemented by us.
Once the crown is made, the temporary crown is removed and the crown is checked for fit. Sometimes this will involve a radiograph. Once the fit is checked the crown is cemented to the prepared tooth.
How long will my crown last?
If crowns are looked after well they should last a very long time. However, crowns are susceptible to the same problems of natural teeth. If crowns are not looked after by flossing and brushing twice a day, then decay can get underneath the crown.
Therefore, it is important to practice good oral hygiene and regularly attend the Dentist to ensure the longevity of your crown.
Sometimes the porcelain can chip off the crown if too much force has been applied by eating food that is too hard, grinding or clenching.
The main three types of crowns are:
All Porcelain Crowns
These are the most aesthetic crowns as they “shine” like natural teeth owing to the greater translucency of porcelain. Light can pass through All-porcelain crowns the same way as natural tooth.
All porcelain crowns are usually placed on front teeth where aesthetics is the highest priority.
Sometimes where chewing forces are excessive All-porcelain crowns are not recommended as the porcelain can chip or fracture.
Porcelain and Metal crowns
The porcelain is fused to the metal making the porcelain metal crown. The metal is on the inside and porcelain covering it on the outside. The porcelain gives the aesthetics and the metal gives the crown the strength. Porcelain metal crowns are made where aesthetics is still important but the tooth needs to be as strong as possible, possibly because the tooth is very weak or heavy chewing forces. As a result of the metal, porcelain metal crowns do not have the same translucency as all-porcelain crowns but are stronger. Aesthetics sometimes can be slightly compromised but Lab Technicians can custom make the tooth to help overcome these problems.
Gold crowns have been used for many decades and are still the strongest and most durable crowns. Gold is soft on opposing teeth and wears like tooth, making gold crowns the choice for grinders and very back teeth.
Gold crowns are also useful as minimal reduction of the tooth is required.
However, gold crowns are not the most cosmetic but very strong and provide an excellent choice for back teeth.
Any surgical or invasive procedure carries risks. Before proceding you should seek a second opinion from an appropriately qualified practitioner.