Dental fillings

What is a dental filling?

Decay is caused by bacteria turning sugar into acid, which dissolves the mineral in enamel. Early on that damage can still repair itself with fluoride and less frequent sugar. Once the surface breaks and a hole forms, it cannot, and the only way to stop it spreading is to remove the decayed tissue and seal the tooth. That is what a filling does. The reason we push people towards check-ups rather than waiting for pain is that decay does not hurt until it is deep. By the time a tooth aches, the bacteria are usually close to the nerve, and the conversation changes from a filling to root canal treatment or losing the tooth. A filling caught early is the small version of a problem that gets expensive in stages. The fillings we place are tooth-coloured and bonded to the tooth. Because they bond, less healthy tooth has to be cut away to hold them, which matters on a tooth that may need more work in twenty years. They set hard during the appointment, so there is no waiting period before you can eat. A filling is a repair and not a new tooth, so it is worth knowing what can go wrong: the tooth can be sensitive for a while afterwards, particularly to cold; a filling can chip or wear at the edge; and decay can start again where the filling meets tooth if that margin is not kept clean. None of that is unusual, and all of it is easier to deal with early, which is the argument for having the tooth looked at rather than waiting to see. There is also a point where a filling is the wrong answer. A tooth that is mostly filling has little of its own structure left holding it together, and another filling can make it more likely to split rather than less. Where decay has reached the nerve, cleaning it out will not settle it. Your dentist should tell you plainly which of those situations you are in, and why, before anything starts.

When might you need a filling?

• Decay found at a check-up

  The most common reason, and the one with no symptoms. Decay between teeth is usually found on an x-ray before you would ever feel it.

• A chip or a small break

  A corner off a tooth, or a piece lost biting something hard. Small breaks are often repaired the same way decay is.

• A filling that has broken or come out

  The tooth underneath is exposed and collects food. It is not usually an emergency, but it gets worse rather than better.

• Sensitivity in one particular tooth

  Sharp reactions to cold or sweet in one spot, rather than a general sensitivity across several teeth.

• Wear or a notch at the gum line

  Often from brushing hard or from acid. Filling the notch protects the softer root surface underneath and settles the sensitivity.

• A tooth that catches floss or traps food

  Floss shredding in the same spot usually means a rough edge or a cavity between the teeth.

What happens, in short

1. Examination and x-rays

   The dentist checks how deep the decay goes and whether the nerve is involved, because that decides whether a filling is the right treatment at all.

2. Numbing the tooth

   Local anaesthetic, given once you know what is planned. Small, shallow fillings are sometimes done without it if you would rather.

3. Removing the decay

   Only the softened, infected tissue comes out. The aim is to keep as much healthy tooth as possible, not to make a tidy shape.

4. Building the filling

   The tooth is cleaned and dried, the material is bonded in and built up in layers, and each layer is set with a light.

5. Checking the bite and polishing

   You bite together so any high spot can be adjusted, then the filling is shaped and polished. A filling left high aches when you chew.

What does it cost?

Fillings at Y3 Smiles Dental start from $200. What you pay depends on how big the repair is and how many surfaces of the tooth it covers, which is why the quote comes after the examination rather than over the phone. You get it in writing, itemised with item numbers, so you can check it against your cover before you agree. If your extras policy includes general dental, a filling is usually claimable and we claim on the spot through HICAPS so you only pay the gap.

You get a written, itemised quote with item numbers before any treatment starts, so you can check it with your health fund. Health funds · Payment options

How do you know if you need a filling?

Usually you do not, which is the point of check-ups. Most fillings are for decay found on an examination or an x-ray before it causes any symptoms.

Decay between teeth is invisible from the outside and only shows on an x-ray. By the time a tooth is sensitive or sore, the decay is generally deep. That does not mean something is badly wrong if you have symptoms, but it does mean the tooth is further along than it would have been at a check-up.

Does having a filling hurt?

The tooth is numb, so you feel pressure and vibration rather than pain. The injection is the part most people notice.

Tell us if you are anxious about it, because there are things we do differently when we know: numbing the gum first, going slower, agreeing a signal that stops everything. Our nervous patients page covers the rest.

Why tooth-coloured rather than silver?

Because a bonded filling needs less healthy tooth removed to hold it in place, and because it matches. Y3 Smiles Dental places tooth-coloured fillings only, not amalgam.

A silver amalgam filling is held in by its shape, so the cavity has to be cut to lock it in, sometimes removing sound tooth to do it. A tooth-coloured filling bonds to the tooth itself, so the preparation can follow the decay instead. Amalgam is also being phased down worldwide under an international agreement on mercury, with a 2034 date set for general use.

Should you replace old silver fillings?

Not for the sake of it. An amalgam filling that is sound and sealed is doing its job, and replacing it removes more tooth. We do replace amalgam where it is reasonable and clinically indicated.

The Australian Dental Association's position is that there is no evidence that replacing sound amalgam fillings with other materials, where there is no clinical reason to, produces a better health outcome. The reasons to replace one are clinical: it has broken, decay has started underneath, or the tooth around it has cracked. Appearance is a legitimate reason to want it changed, and that is your decision, but it should be made knowing that a replacement is a bigger cavity than the original.

How long does a filling last?

There is no honest single answer. It depends on how large it is, where it sits in the bite, and how well the margin is kept clean.

A small filling in a tooth that is otherwise healthy is in a very different situation from a large one rebuilding a back tooth that takes heavy chewing. Anyone quoting you a number for fillings in general is quoting an average that may have nothing to do with your tooth. What we can tell you is what yours looks like at each check-up, while there is still time to do something small about it.

When is a filling not the right answer?

When there is not enough tooth left to hold one, or when the decay has already reached the nerve.

A tooth that is mostly filling can split under normal chewing, and at that point a crown or an onlay protects it better than more filling material would. Where the nerve is infected, the tooth needs root canal treatment first. Those are bigger treatments and they should be explained as a choice rather than presented as the only option.

What happens if decay is left alone?

It keeps going. Decay does not stop or reverse once the surface has broken, and it works towards the nerve.

The stages have costs attached to them, and each one is larger than the last: a filling, then a root canal and a crown, then removing the tooth and deciding whether to replace it. The cheapest point to deal with decay is always the first one.

Symptoms that can lead here

• Lost filling or crown
• Toothache
• Sensitive teeth
• Broken or chipped tooth
• White spots on teeth

More about dental fillings

• filling vs crown
• Night splints