Dental fillings are used to repair teeth from the damage caused by cavities (tooth decay) or fracture. While there are several types of filling materials available, we find that the most popular are the tooth- coloured varieties.
Composite resin is a dental plastic used to fill small to moderate sized cavities or fractures. The cavity or fracture site is prepared (usually under a local anaesthetic), and the composite is carefully shaped and bonded directly to the tooth. The result is a moderately-strong filling with generally pleasing cosmetic results.
Composite resin is not as strong as the enamel of teeth, so it can wear down, chip or crack under some circumstances. It is also more porous than enamel, and can pick up stains from foods and beverages, or from activities like cigarette smoking. Fortunately, it is usually quite straightforward to repair or replace a damaged or stained composite resin filling.
Composite resin is generally not ideal for very large fillings in the back teeth, because it lacks the strength to withstand the wear and tear that large fillings are exposed to.
Dental Ceramics (Porcelain)
If a cavity or fracture is moderately large and a tooth-coloured option is preferred, the ideal material is generally dental ceramic. In this case, the filling would now be called an Onlay (or sometimes an Inlay).
A porcelain onlay requires two appointments because the onlay itself must be built by a dental ceramist in their laboratory. During the first appointment, the cavity or fracture site is cleaned and shaped. An impression of the tooth will then be made; this allows the ceramist to create an exact replica of the prepared tooth. It is on this model that the ceramist will build the porcelain onlay. At the end of the first appointment, a temporary onlay is made to fill the cavity.
At the second appointment, the temporary onlay will be removed and the porcelain onlay will be bonded into place.
Porcelain has a very similar appearance to enamel, so porcelain onlays often have an excellent cosmetic appearance, and can be virtually indistinguishable from natural teeth.
Porcelain is much stronger than composite resin, but still not as strong as tooth enamel. It is possible for porcelain onlays to chip, break or wear down over time. In some cases, repair is possible, but a severe fracture may necessitate replacement of the onlay.
Care Of Your Fillings
Whilst fillings themselves cannot decay, the teeth underneath them can, so it is critical to keep your filled teeth very clean by brushing and flossing regularly.