A crown is a porcelain, metal or zirconia “cap” adhered to the tooth stump. The dentist will prepare the tooth for a crown by reducing an even amount of tooth structure all around. The crown will then fit over the stump of the tooth.
- Various materials such as porcelain, metal, zirconia or gold
- Normally covers compromised dentition, but can also be used to open up the vertical height in a bite (see Neuromuscular Dentistry)
- A “cap” adhered to the tooth stump
Crowns can be made from a variety of materials. Traditional materials such as gold and porcelain fused to metal crowns are still common today, but there is a new material on the market that is stronger, very bio-compatible and not abrasive to other dentition. This newcomer is called zirconia. It also has other medical uses such as hip replacements. A crown made from zirconia is superior in strength to any other material on the market today.
A normal crown made with a metal base has porcelain fused to the top layer. This porcelain is weak, and as with other porcelain restorations, it is subject to chipping or fracture if the bite is compromised. A product called e-max ® (lithium dissilicate), is stronger than porcelain at 400MPa, but zirconia is stronger again with 1200MPa. We also offer several options with zirconia at our laboratory. Option 1 – solid zirconia crown (strongest) is stained only. This is perfect for the posterior teeth, where aesthetics are not as important and function is very important. Option 2 – zirconia crown with buccal veneering where the crown is solid zirconia except for the front facing, which is layered in porcelain. This gives the crown a highly aesthetic look, whilst all the functional surfaces of the crown are still in high strength solid zirconia. Perfect for the anterior teeth.
Your Dentist may tell you that zirconia is not suitable for some types of restorations due to the lack of retention for the crown to bond to the remaining tooth structure. There is a difference between bonding and cementing a crown to the tooth stump, but without becoming too technical, there is now a product on the market that allows the bonding of zirconia in most circumstances. It is called Hotbond, and you should ask your dentist if they have heard of it.
A crown adhered to the tooth in favourable conditions can last a lifetime.
Crown insert step by step
- Step 01: Clinical consult at Dentist where a crown is prescribed and impressions taken
- Step 02: Attend the Lab for a colour match (if required)
- Syep 03: Crown is produced in Lab
- Step 04: Insertion of crown at Dentist surgery