Your oral health and your child’s

You may have heard that poor oral hygiene can be passed on to your child, and wondered what you might be handing down. There is no blame in the answer. A 2015 review found that a bacterium linked to decay can pass from a mother to her child. A child’s teeth are also affected by what they eat and drink and how well they are cleaned, and you can influence both from the first tooth.

Can bacteria pass from a parent to a child?

The NHS says tooth decay happens when bacteria create a sticky layer called plaque over the teeth, which damages the tooth surface over time.

A 2015 systematic review looked at studies of mothers and their children. It found evidence that Streptococcus mutans, one of the bacteria associated with tooth decay, passes from mother to child. The studies compared the genetic strains of the bacterium in each pair. The review looked only at mothers and their children, so it cannot tell us about fathers or other carers.

That is as far as this review goes. It asked whether the bacterium passes between mother and child, not whether a child who picks it up will go on to have decay. The NHS says decay is often caused by having too much sugary food and drink and not cleaning teeth and gums regularly. Those are habits, and habits can change at any point.

Dummies

One practical step comes from a children’s oral health page on a west London NHS website: never suck your baby’s dummy to clean it, because this spreads germs between you and your baby. It suggests keeping plenty of spare dummies. The NHS also says not to dip a dummy in anything sweet, such as sugar or jam.

The same page adds that frequent dummy use, thumb sucking, or bottle use beyond 12 months can leave a gap in the top front teeth. It suggests limiting a dummy to when your baby needs it most. Our guide to lisps in children looks at what the sources say about dummies and speech.

That advice is about teeth. NHS safer sleep advice says to think about using a dummy to settle your baby to sleep, because some research suggests this can help lower the risk of sudden infant death syndrome (SIDS). Ask your health visitor if you are unsure.

Habits you can share

Setting a good example helps, the NHS says, so let your baby see you brushing your own teeth. It also suggests taking your child along to your own dental appointments so the setting becomes familiar, and checking the whole family’s sugar intake rather than only your child’s.

Brushing from the first tooth

Start as soon as the first milk tooth breaks through, which is usually at around 6 months but can be earlier or later. Fluoride toothpaste is important, because it helps prevent and control tooth decay. The age guide below follows NHS and government advice.

Age	Toothpaste	Who brushes
Under 3	A smear	A parent or carer
3 to 6	A pea-sized amount	You help and supervise as your child brushes
7 and over	Fluoride toothpaste	Your child, with you watching

For 3 to 6 year olds, the NHS says to encourage your child to brush their own teeth while you supervise. The government toolkit for dental teams says a parent or carer should brush, and help your child do more of it themselves as they get older. So at this age, stay close and be ready to help.

• Brush twice a day for about 2 minutes: last thing at night, and at least once more.
• Spit out afterwards and do not rinse, which would make the fluoride work less well.
• Do not let your child eat or lick toothpaste from the tube.
• Keep helping until you are sure your child can brush well enough alone, which is normally at least age 7. If they resist, try making it a game, for example by brushing your own teeth at the same time.

Toothpaste comes in different fluoride strengths, measured in parts per million (ppm), so check the box. NHS figures are at least 1,000ppm up to age 3, 1,000 to 1,500ppm from 3 to 6, and 1,350 to 1,500ppm from 7. If you are unsure which toothpaste suits your child, ask your dentist.

Food and drink

According to the NHS, sugar causes tooth decay, and it is not only the amount that matters but how long and how often teeth are in contact with it. The sugars in whole fruit and milk are less likely to cause decay. Our guide to sugar and your teeth has the daily limits by age.

For drinks, the NHS names plain milk and water for young children. Bottles are fine for expressed breast milk, formula or cooled boiled water, but juice or sugary drinks in a bottle can increase decay. From 6 months you can offer drinks in a free-flowing cup without a valve. Government guidance for dental teams says to discourage feeding from a bottle from the age of 1.

If you give fruit juice, the NHS advises keeping it to mealtimes, mixing 1 part juice with 10 parts water, and giving no more than one 150ml drink a day.

Night-time matters too. Government guidance says to avoid sugary food and drink at bedtime, when saliva flow is reduced. The NHS says to give only breast milk, formula or cooled boiled water at bedtime or overnight. If your child needs medicine, ask a pharmacist or GP whether there is a sugar-free option.

What happens at the dentist?

Take your child when their first milk teeth appear, or before they are 12 months old, the NHS advises. Our guide to your child’s first dental visit says what to expect. The dentist can advise on preventing decay and spot problems early, and just opening a child’s mouth for a look is useful practice. After that, go for check-ups as your dentist advises.

From the age of 3, children should be offered fluoride varnish at least twice a year, according to the NHS. Fissure sealants, a thin plastic coating on the chewing surface of the back teeth, can protect them from decay once the adult back teeth come through, usually at about 6 or 7. Ask your dentist about both.

How common is decay in children?

The Office for Health Improvement and Disparities surveys 5 year olds at mainstream state schools in England. In its 2023 to 2024 survey, 22.4 percent had experience of obvious decay. That means visible decay that had gone deeper than the enamel, or a tooth already filled or missing because of decay. In the most deprived fifth of areas the figure was 32.2 percent, against 13.6 percent in the least deprived fifth. The report calls decay a preventable disease, and says poor oral health in children can lead to pain, infection, and difficulty with eating, sleeping, playing and socialising.

If your child has a decayed tooth, you are far from the only parent, and a dentist can help.

When to see a dentist

The NHS says to see a dentist as soon as possible if you think your child has tooth decay, and that decay may cause no symptoms at first.

A swollen face or jaw, intense pain or a high temperature can be signs of a dental abscess, a build-up of pus caused by infection. The NHS says an abscess needs urgent treatment by a dentist and will not go away on its own. It advises asking for an urgent dentist appointment or getting help from NHS 111, and not going to a GP surgery, because a GP cannot give dental treatment.

For your child, the NHS says to call 999 or go to A&E if you see any of the signs below.

What we would do

We are a private practice and are not accepting NHS patients, so the free NHS dental care for children applies at NHS dentists, not here.

Our children’s dentistry page explains how we look after children from their first visit, keeping appointments short and unhurried and paced to how your child is feeling. Our children’s membership plans cover two dental examinations a year and general dentistry, including scale and polish, fillings and extractions where the dentist judges them necessary. Fluoride varnish and fissure sealants are not among the treatments listed on our site, so ask your practice what is available for your child.

To arrange an examination for your child, book a check-up.

Want us to take a look?

Book an appointment at whichever of our five practices suits you. We will check what is going on and talk you through your options.

Book an appointment Read about our children’s dentistry