DENTAL CROWNS EXPLAINED
Dental crowns can be used for patients who have heavily worn, chipped or broken teeth. Find out more about the reasons you might need a crown, different crown materials, the treatment steps, and the crown costs.
Dental crowns (sometimes called “caps”) are thin coverings of dental material that are used to completely cover the visible portion of the tooth around and above the gum. A crown is used to restore the size, strength, shape or appearance of a tooth to maintain function and aesthetics.
WHEN DO I NEED A CROWN?
There are usually three reasons for the placement of crowns:
- The tooth is so badly damaged by toothwear, dental decay or fillings that it is best saved by using a crown
- Following root canal therapy, to preserve the strength in remaining tooth structure. This is because a root canal treated tooth is significantly weakened by the drilling process during root canal therapy
- The tooth is being used as an abutment (support) for a bridge or denture to replace missing teeth
COST OF CROWNS
The costs of our dental crowns are outlined in the table below:
Two: from $1,350 each
Three: from $1,300 each
TREATMENT PROCESS OF DENTAL CROWNS
There are generally three phases to having a crown made for your tooth but you only need to attend for two appointments:
- Preparing (drilling) the tooth in an appropriate fashion for the type of crown chosen. This may involve removing the old filling material, removing the decayed tooth structure or removing cracked or damaged tooth. As a minimum, enough material needs to be removed to create enough space for the replacement crown material. Sometimes, because of the position of the soft tissue (gums), it may be necessary to trim or shape the soft tissue around the teeth with specialised instruments or “retraction cord”. This makes it easier to achieve a good impression (digital scan or with impression material) as well as allowing us to create better aesthetics.
- Making impressions of the prepared tooth, opposing teeth, and the occlusal (bite) relationships to transfer the information to the laboratory. This can be done using a digital scanner, which captures the relevant information and sends it to the laboratory for digital design and fabrication, or it can be done with more the more traditional impression material.
- Selecting a shade for tooth-coloured crowns.
- A temporary or provisional crown is used to protect the tooth whilst the laboratory makes the final crown.
- Fabricate and polish the crown. The laboratory custom makes your crown from the information transferred to them.
- Cementing or bonding the completed crown into position. Once the crown returns from the laboratory it is cemented or bonded onto the tooth or teeth with specialised dental cement. “Cementing” a crown is the traditional method of holding a crown onto the tooth and relies on physical grip between the crown, cement and tooth. “Bonding” a crown into position requires a chemical bond between the tooth, cement and crown and is the modern method used with porcelain crowns. Some adjustments may be required to finalise the fit.
TYPES OF CROWN MATERIAL
Different materials are used in different situations, which your dentist will discuss with you. Crowns can be made of many different materials; however, there are 3 main types of crown materials:
- Full porcelain crown: These types of crowns are the most popular and modern. Full porcelain crowns approximate the total appearance of an undamaged, natural tooth more closely than any other type of crown. With today’s adhesive technology, these restorations are most often bonded into place with an enamel and dentine bonding agent. They are made from zirconia or lithium di-silicate (the most popular is IPS e.max).
- Full gold (full cast crown): This type of crown is more traditional and involves making the full crown out of gold or a cast metal. The advantage of a full gold crown is that it is very difficult to chip or damage the crown through misuse. However, they are gold/yellow in colour and not as popular nowadays due to the advancement of modern dental materials.
- Porcelain fused to metal crown: A porcelain-fused-to-metal (PFM or VMK) crowns consists of a metal-alloy base (known as a coping) partially or fully covered by porcelain. Since the metal is covered with a layer of porcelain, it has a much more natural appearance than a gold casting and more closely resembles a natural tooth. The biggest disadvantage of these types of crowns is that the junction between porcelain and metal is a weak point and prone to chipping, or de-laminating.
The White Bite primarily uses full porcelain crowns made from zirconia or lithium di-silicate (like IPS e.max) due to their superior performance and longevity.
LONGEVITY OF CROWNS
Crowns last on average 15 years but can last much longer. It is not uncommon to see crowns that are over 20 years old that are still functioning. The longevity of a crown is dependent on maintaining a high level of oral hygiene, regular dental visits and the pre-treatment condition of the tooth. Anything that would damage your teeth can also damage your crown, this includes trauma (e.g. sporting, punch, accident etc.); biting on a fork; tearing plastic packets/covers open; chewing on hard things like ice, fingernails or pens. We recommend chopping up hard foods into smaller pieces to reduce the risk of damage to your crowns.