Tooth-Coloured (Composite) Fillings

A tooth-coloured filling closes the space left in a tooth once decay has been removed or a broken piece has been tidied up, using composite resin that matches the colour of the tooth. Composite is a resin filled with fine particles of glass and ceramic; it is bonded to the tooth with a special adhesive and hardened with a blue curing light. It is what most people call a "white filling".

This page is about fillings after decay or damage. The same material is used on healthy front teeth to change their shape, close gaps or correct their colour, but that solves a different problem; we cover it separately on the composite bonding page.

Composite or amalgam: what is the difference?

Amalgam, the grey or "black" filling, does not stick to the tooth. It is packed into the cavity and only stays in place if the cavity is shaped so that the filling cannot come out, which often means removing some healthy tooth as well. Because composite bonds to the tooth, usually only the decayed part has to be removed and the cavity stays small. The trade-off is that it takes longer to place, it is very sensitive to moisture, and the result depends directly on the dentist's workmanship.

Should I replace my old amalgam fillings?

Not always. If an amalgam has sound edges, has no decay underneath and has not cracked the tooth, we do not recommend removing it just because "it contains mercury", and many health authorities take the same view. Removing it releases some vapour in itself, and every replacement takes a little more tooth with it. During pregnancy it is right to postpone any amalgam replacement that is not essential. When replacement is needed, we cut the amalgam into sections and lift it out under plenty of water and strong suction, to keep vapour and particles to a minimum. These are the situations where replacing it is worthwhile:

• There is new decay at the edge of the filling or underneath it.
• The filling has broken, or gaps have opened along its edges.
• Crack lines have appeared in the tooth walls next to the filling, and you feel a sudden, sharp twinge when you bite.
• You do not want to see grey on a tooth that shows when you smile. That is a legitimate cosmetic choice, but it should be made knowing that replacement will take a little more tooth.

One note: over the years amalgam can stain the dentine underneath it grey. That colour does not always disappear completely when the filling comes out; rather than drilling away tissue that is sound but stained, we cover it with a layer of opaque composite.

How is a filling placed, step by step?

1. Choosing the shade. This is done before the tooth dries out. A dry tooth temporarily looks lighter and leads to the wrong shade.
2. Numbing and cleaning. The decay is removed under local anaesthetic; you usually feel no pain during the procedure. Very shallow decay may not need an anaesthetic at all.
3. Isolation. Saliva weakens the bond of the composite, so the tooth is kept dry with a rubber dam or cotton rolls. On back teeth a thin band (a matrix) is placed to create a tight contact with the neighbouring tooth; if that contact is left loose, food gets trapped between the teeth.
4. Layering. Adhesive is applied to the surface, then the composite is placed in thin layers and each layer is cured separately. This reduces the shrinkage that happens as composite sets, and it lets us imitate the darker dentine inside and the more translucent enamel on the outside.
5. Bite adjustment and polishing. We check how your teeth meet, leave no high spots and polish the surface.

If the cavity is very large, is a filling still the answer?

Composite has its limits. The larger the cavity, the greater the shrinkage stress as it sets, the harder it is to create a tight contact with the neighbouring tooth, and the more of the chewing load the filling itself starts to carry. If one of the tooth's chewing cusps has broken off or become very thin, or the cavity is wider than roughly half the width of the tooth, a large composite can eventually crack the tooth itself. In that case a porcelain inlay or onlay, made in a laboratory and bonded in place, protects the tooth better; if most of the tooth has been lost, a crown comes into the picture. If the decay has reached the nerve, the problem is no longer one for a filling: root canal treatment is needed first, and the filling comes after it.

Is sensitivity after a filling normal?

After a deep filling, mild sensitivity to cold and to biting can last a few days, sometimes a few weeks, and fades on its own. If the filled tooth touches before the others when you bite, the filling has been left high; it takes a few minutes to adjust, so do not wait. If you are already back home, your local dentist can make the adjustment. Pain that starts on its own, throbs or wakes you at night, on the other hand, suggests that the nerve has been affected, and it should be checked.

How long does it last, and what affects the cost?

Studies show that most well-placed composite fillings in back teeth work without problems for many years. Two things shorten their life the most: new decay starting at the edges, and clenching. Staining that appears along the edges over time can usually be dealt with by polishing or a small repair, without replacing the whole filling. The cost depends on how many surfaces of the tooth the filling covers, how deep it is and whether the tooth needs another procedure first. At our clinic in Bayraklı, İzmir, you receive a written, itemised quote after the examination and, where needed, an X-ray. Whether any of it is covered by insurance depends on your own policy, so check with your insurer.