A porcelain crown is sometimes called a cap, and covers the entire tooth, right down to the gum line, completely sealing up the tooth. When correctly fabricated, a porcelain crown will closely replicate a natural tooth, helping to restore strength and integrity to a tooth that has been badly damaged due to decay or trauma.
Your new porcelain crown will be a similar shape and size to the original tooth, but it can be constructed in such a way as to help improve overall appearance. This means if your existing tooth had any flaws or was severely discoloured, the new porcelain crown can be made to help cosmetically improve tooth appearance. Modern porcelains are strong and beautiful and can reproduce the complex combination of hues, shades and translucency found in natural teeth.
Why Might I Need a Porcelain Crown?
There are a number of different circumstances that may mean you require a porcelain crown. These include:
To protect and restore a tooth that has become severely worn or broken down
To protect a tooth weakened due to trauma or decay
To provide additional support to a tooth that has a very large filling and little natural tooth structure remaining
To cover up a misshapen or discoloured tooth
As the final restoration during dental implant treatment
As part of a cosmetic smile makeover
To support a dental bridge
All-ceramic crowns are entirely metal-free, and can be pressed from a single ingot of porcelain, or they may have a substructure made from a material called zirconia. Pressed crowns are first created in wax before being pressed. The crown is then finished and characterised with special porcelains. Zirconia crowns are milled from a solid block using CAD/CAM technology, before being sintered or baked at very high temperatures. The result is an incredibly strong substructure that can be used to make single crowns, but which is strong enough to create large span bridges replacing multiple teeth. The substructure is either white or tooth coloured, and is then covered with compatible porcelain.
Pressed crowns tend to be most useful for crowning teeth that are not subjected to such strong biting and chewing forces, whereas zirconia crowns are suitable for teeth anywhere in the mouth, including molars.
Both types of crowns will provide excellent aesthetic results that are superior to porcelain fused to metal crowns. This is because the metal base in porcelain fused to metal crowns prevents the light from being transmitted right through the crown, but it can pass right through in the metal free crowns in a way that is very similar to natural teeth. The result is a crown that is very translucent and life-like. Metal free crowns are also ideal for anyone who has a metal allergy.
What is the Process for Having a Porcelain Crown?
You will probably need three visits to Sparkle Dental; the first will be an examination and discussion of treatment required, the second will be to prepare the tooth, and the third will be to fit the tooth.
Tooth preparation is generally carried out using a local anaesthetic to numb the area being treated, but if you are particularly anxious then we can provide extra sedation to keep you comfortable and relaxed. It is necessary for your dentist to cut away any decayed tooth structure, and to shape the tooth to receive the crown. If there is a substantial amount of tooth structure already missing from the tooth then your dentist might need to build up the tooth to help support the crown.
The next step will be to take an impression of the tooth using impression material in a mouth tray. Once the impression tray is removed your tooth will be protected with a temporary crown. You will need to take a little extra care with your temporary crown and it's best to avoid chewing anything to sticky or too hard as it is only held in place with temporary cement. When flossing around your temporary crown take care to slide the floss out rather than to pull it straight up as this could dislodge your temporary crown.
Your dental impressions are sent to a dental laboratory where they are cast up in special dental plaster, providing a highly detailed replica of your teeth. This model is used to fabricate your porcelain crown, and once completed it will be returned to your dentist. This process will usually take a couple of weeks or possibly slightly longer depending on the type of crown.
The final step will be for your temporary crown to be removed so your new crown can be fitted, and this is likely to be carried out under local anaesthetic. Sometimes it is necessary to make small adjustments to get the fit absolutely perfect before it is permanently cemented into position. It is normal to feel a little bit of sensitivity immediately after your crown is fitted but it should soon settle down.
Caring for Your Porcelain Crown
You can brush and floss your porcelain crown in exactly the same way as you do your natural teeth, and it's very important to make sure you floss thoroughly around all the margins of the crown to keep it free from plaque and to keep your gums healthy.
Regular check-ups and professional cleanings at Sparkle Dental combined with good home care will help prolong the life of your porcelain crown. Porcelain crowns can last anywhere from 5 to 15 years or possibly even longer before they need replacing. The exact length of time depends on oral hygiene and other habits such as teeth grinding that could potentially damage the crown.