Tooth decay

Tooth decay starts when plaque builds up on your teeth and produces acid. The acid causes holes, also called cavities, in the teeth (dental caries).

If tooth decay isn't treated, it gets worse and can lead to abscesses, which are collections of pus at the end of the teeth or in the gums. Plaque is also involved in gum disease.

When plaque is allowed to build up, it can lead to further problems, such as:

• dental caries (holes in the teeth)
• gum disease
• dental abscesses (collections of pus at the end of the teeth or in the gums)

Tooth decay may not cause any pain at all. But if you have dental caries, you might notice one or more of these:

• toothache, either a continuous pain that keeps you awake or an occasional sharp pain with no obvious cause
• tooth sensitivity, where you may feel tenderness or pain when eating or drinking something hot, cold or sweet
• grey, brown or black spots appearing on your teeth
• bad breath
• an unpleasant taste in your mouth

See your dentist regularly, so that tooth decay can be treated as early as possible and steps to prevent decay can begin. Tooth decay is much easier and cheaper to treat in its early stages. A dentist can usually spot decay, and any further problems, with a simple examination or an X-ray.

Regular dental check-ups matter too. Adults should have a check-up anywhere between every 3 months and every 2 years, depending on their needs.

Take your child to the dental clinic routinely, as your dental team advises.

How your tooth decay is treated depends on how far it has gone.

If the decay is at an early stage, your dentist will talk to you about how much sugar is in your diet and when you eat. They may also put a fluoride gel, varnish or paste on the area. Fluoride protects your teeth by strengthening the enamel, so the teeth stand up better to the acids from plaque that can cause tooth decay.

For more advanced decay, your dentist may talk to you about a filling or a crown. The dentist removes the decay, offers a local anaesthetic to numb the tooth, and then fills the hole.

Sometimes the decay spreads to the pulp, which is in the centre of the tooth and contains blood and nerves. In that case the pulp may be removed in a process known as root canal treatment.

If the tooth is so badly damaged that it can't be restored, it may need to be taken out. Your dentist may be able to replace it with a partial denture or a bridge.

Tooth decay is a common problem, but it's often entirely preventable. The best way to avoid it is to keep your teeth and gums as healthy as possible.

• visit your dentist regularly, and your dentist will decide how often they need to see you, based on the condition of your mouth, teeth and gums
• cut down on sugary food and drinks, particularly between meals or within an hour of going to bed (some medicines can also contain sugar, so it's best to look for sugar-free alternatives where possible)
• look after your teeth and gums by brushing your teeth properly with a fluoride toothpaste twice a day, and using interdental brushes or floss daily
• avoid smoking or drinking alcohol excessively, because tobacco can interfere with saliva production, which helps to keep your teeth clean, and alcohol can contribute to the erosion of tooth enamel
• see your dentist or doctor if you have a persistently dry mouth, as this may be caused by certain medicines, treatment or medical conditions

Good eating habits can help your child avoid tooth decay, so limit sugary snacks and drinks. It's also a good idea to encourage regular visits to the dentist from an early age.

Toothbrushing

Start brushing your child's teeth and gums every day as soon as their first tooth grows in.

Advice for keeping children's teeth healthy is grouped by age, and it covers brushing for babies, toddlers and pre-schoolers:

• under 3s
• 3 to 5 year olds
• 5 to 12 year olds

Children should still brush their teeth twice a day, especially before bedtime.

Your mouth is full of bacteria, and they form a film over the teeth called dental plaque. This is where tooth decay begins.

When you eat or drink things high in sugars, the bacteria in the plaque turn the sugars into the energy they need. They produce acid at the same time.

If the plaque is allowed to build up, the acid can begin to break down (dissolve) the surface of your tooth. This causes holes known as cavities.

Once cavities have formed in the enamel, the plaque and bacteria can reach the dentine, the softer, bone-like material underneath. Dentine is softer than enamel, so the decay speeds up.

Without treatment, bacteria will get into the pulp, the soft centre of the tooth that contains nerves and blood vessels. Your nerves are then exposed to the bacteria, and this usually makes the tooth painful.

The bacteria can cause a dental abscess in the pulp, and the infection could spread into the bone.