Laser treatment for cavities: no drill and, most of the time, no injection

How the Er:YAG laser treats cavities, how it differs from the drill, why fillings last longer, what it costs and who it is the best choice for.

How a cavity forms

The bacteria in dental plaque turn the sugar in food into acids. The acids gradually draw minerals out of the enamel, first leaving a dull white spot, then a small cavity. Once the enamel has broken down, the decay advances faster into the softer dentine underneath. Left untreated, it reaches the nerve: then come pain, sensitivity to heat and, eventually, root canal treatment.

A cavity doesn't heal on its own and toothpaste won't stop it. The good news is that, caught early, it can be dealt with in a single short visit, and with the laser, without the unpleasant parts of conventional treatment.

Signs of a cavity you can spot yourself

• a dull white spot or a brown one on a tooth that doesn't go away when you brush;
• brief sensitivity to sweet things, cold or hot food, in a single tooth;
• floss that keeps catching or shredding between the same two teeth;
• food that gets stuck in the same place after every meal;
• a small hole you can feel with your tongue, or a sharp edge on an old filling.

Many cavities, especially those between the teeth, give no sign until they are large. That is why a check-up every 6 months matters even if nothing hurts.

How the laser works on the tooth

The Er:YAG laser emits short pulses of light that water absorbs very strongly. Decayed tissue contains much more water than healthy enamel, so the laser removes it selectively, layer by layer, and practically stops by itself where the tooth is healthy. A fine jet of water cools the area the whole time, which is why the tooth doesn't heat up.

How it differs from the drill

• No vibration and no noise. For many patients, the sound and vibration of the drill are the main reason they put off going to the dentist. The laser only makes a quiet clicking sound.
• Usually no injection. For small and medium cavities, most patients don't need anaesthetic. You leave without a numb lip and can eat straight away.
• More of the tooth is preserved. The drill also removes some of the surrounding healthy tissue to create a geometric shape. The laser removes only what is diseased.
• A sterile cavity. The laser light destroys the bacteria left in the cavity, and the treated surface has a texture that the filling material bonds to very well. The risk of new decay forming under the filling goes down.

What happens during the visit

1. The dentist locates the cavity by examining the tooth and, if needed, with an X-ray.
2. The decayed tissue is removed with the laser. If you feel anything unpleasant, raise your hand and we stop.
3. The edges of the cavity are checked and sterilised.
4. The tooth is rebuilt layer by layer with light-cured composite, in the shade of the neighbouring teeth.
5. The filling is finished and polished, and your bite is checked, so nothing feels “too high”.

A typical cavity is dealt with in 30 to 45 minutes. You can use the tooth straight after the visit.

How much does a laser filling cost?

The difference in price reflects the equipment and the extra time. On the other hand, a filling placed in a sterile cavity usually lasts longer, which means fewer return visits. At the consultation we tell you how big the cavity is and exactly what it will cost, before we start.

When you may still need anaesthetic

For deep cavities very close to the nerve, or for very sensitive teeth, the dentist will ask whether you would like a local anaesthetic. A smaller dose than in conventional treatment is usually enough. The decision is yours: some patients prefer anaesthetic from the start, others only ask for it if they feel something.

Who it is the best choice for

• children, for whom their first experience at the dentist matters for life;
• adults who are afraid of the dentist or of needles;
• pregnant women, for whom we avoid medication as far as possible;
• people with allergies or reactions to anaesthetics;
• anyone who would rather not spend two hours with half their face numb after a filling.

Cavities in children

With children, the laser makes the biggest difference. A child who has heard the drill just once can be left afraid of the dentist for years. With the laser, a cavity in a baby tooth is dealt with in 15 to 20 minutes, usually without an injection. A child's first visit to us, however, is only for getting to know us, with no treatment at all, so they can get used to the clinic.

How to prevent new cavities

Brushing twice a day for at least two minutes with a fluoride toothpaste is still the foundation. Clean between your teeth every day too, with floss, interdental brushes or a water flosser: that is where most cavities in adults appear. Cut down on sweet snacks and fizzy drinks between meals; what matters most is not how much sugar you have but how many times a day you have it. A professional cleaning and a check-up every 6 months catch cavities while they are still just spots, which is when they are easiest to treat. In children, sealing the fissures of the permanent molars prevents most cavities in that area.

Frequently asked questions