Crowns, Bridges & Inlays
WHAT IS A CROWN?
A crown is a cap that is placed over a tooth and held in place by dental adhesive or cement.
Crowns are used for several reasons:
as a protective cover for badly decayed teeth or fractured teeth
as a permanent restoration for teeth with large fillings
to correct minor problems in natural teeth like spacing and irregular shape or severe discolouration.
WHAT ARE CROWNS MADE FROM?
Crowns can be made from a variety of materials. They can be made from plastic, ceramic or metal alloys. A combination of metal and ceramic is also possible to maximise strength and simulate the appearance of natural teeth.
HOW ARE CROWNS MADE?
Firstly, a thorough clinical examination is conducted with radiographs, by the dentist. The suitability for crowns is assessed and any preparatory work is carried out. Your dentist will also be able to advise on material choices, treatment sequence and any other concerns you may have.
At the second appointment, the teeth to be crowned are prepared. This involves reduction of the tooth size (usually under local anaesthesia) followed by an impression or mould of the prepared tooth. This trimming of the tooth is required to create space for the crown to be fitted. The mould taken is then sent to a laboratory where skilled technicians will fabricate the crown. In the meantime, a temporary crown is made and fitted onto the trimmed tooth.
At the third appointment, the temporary crown is removed, and the tooth surfaces cleaned. The completed crown is tried on the tooth for fit, harmony with the bite, and appearance. Finally, the crown is cemented onto the prepared tooth with dental cement.
HOW LONG DO CROWNS LAST AND HOW DO I CARE FOR THEM?
Crowns are made of inert materials that do not deteriorate over time. However, the underlying tooth is still prone to decay and gum disease.
Ceramic on the surface may chip or fracture. Avoid chewing excessively hard substances like ice or bones. Daily brushing and flossing are essential for maintaining good oral health as well as keeping the crown trouble-free. The most vulnerable portion of the crown is the margin or the junction between tooth and crown.
Regular check-ups will enable your dentist to detect any problems with your crown and recommend necessary treatment.
Porcelain (tooth coloured) inlays and onlays are restorations placed usually on the chewing surfaces of the back teeth.
An inlay fits within the confines of the teeth. An onlay covers the entire chewing surface of the tooth. These can be made of either plastic resin or porcelain.
The procedure involves removing decayed tooth structure or old fillings, preparing the tooth cavity, taking an impression of the cavity to fabricate a custom-fit inlay or onlay. Two visits are required to complete the treatment.
WHAT ARE BRIDGES MADE OF?
Bridges are usually made of a precious metal. If the bridge will show, porcelain is then bonded to the base. Sometimes, there are other non-precious metals used in the base for strength.
ARE BRIDGES EXPENSIVE?
Although a bridge may seem costly they can be a wise investment that will give many years of good service. It will also improve your appearance and bite. A bridge uses the considerable skill of the dentist and technician, and in this way, it's similar to ordering a piece of hand-made jewellery.
HOW DO I LOOK AFTER MY BRIDGE?
You need to clean your bridge every day, to prevent problems such as bad breath and gum disease. You also have to clean under the false tooth every day. Your dentist or hygienist will show you how to use a bridge needle or special floss, as a normal toothbrush cannot reach.
Veneers are thin, custom-made shells crafted of tooth-coloured materials designed to cover the front side of teeth to improve the overall appearance of teeth. They are made of either thin plastic resin or porcelain and can be placed to:
correct poorly formed or mildly mal-positioned teeth
close gaps between teeth
mask internal stains
restore partially broken-down teeth
Tooth preparation is minimal and confined to the enamel structure. The veneer is bonded to the tooth structure with tooth-coloured resin cement. Several visits are necessary to complete treatment.
Patients should be aware that this is usually an irreversible process because it's necessary to remove a small amount of enamel from your teeth to accommodate the shell.