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- What is this information about?
- What are the early side effects of cancer treatment, and how could this affect my child's teeth?
- What can I do to help?
- How can I help to reduce the dryness inside my child's mouth?
- How can I help to make my child more comfortable if they have a sore ulcerated mouth?
- Will the cancer treatment affect the adult teeth that are starting to form?
- What do enamel defects look like?
- Can I stop this from happening to my child's teeth?
- Is there anything at home we can do to help protect these teeth?
- How can I reduce my child's risk of getting tooth decay?
- What is the best way to clean my child's teeth?
- Do I need to help my child to brush their teeth?
- What toothpaste should I use to provide the maximum protection for my child's teeth?
- How much toothpaste should I use on my child's toothbrush?
- My child does not like the taste or the feeling of toothpaste in their mouth. What can I do?
- I find it impossible to brush my child's teeth. Is there anything that could make it easier?
- What is the best diet for preventing tooth decay?
- My child will only drink sugary drinks. What can I do?
- What savoury foods can I give my child between mealtimes as a snack?
- How do I maximise protection for my child's teeth?
- What are the main things to remember about looking after my child's teeth?
- Where can I find more information and advice?
What is this information about?
This information tells you about how to best care for your child’s mouth and teeth. Cancer treatment can affect the health of your child’s teeth and mouth. Their cancer treatment can be a difficult and worrying time for you, but it is important to try to keep your child’s teeth healthy during this period.
There are also things that you can do to help your child if their mouth is painful or uncomfortable.
If they wear fixed braces these may need removing before starting cancer treatment. This is to protect teeth and their mouth from developing problems during their treatment.
What are the early side effects of cancer treatment, and how could this affect my child’s teeth?
Early side effects of cancer treatment can be:
- mouth (oral) infections
- dry mouth (xerostomia)
- change in taste
- sore ulcerated mouth (mucositis).
These can make children at higher risk of developing tooth decay, because it can be difficult for them to brush their teeth.
What can I do to help?
It is important to keep your child’s mouth clean and free from tooth decay.
- Try to make sure that your child is on the maximum toothpaste for their age and using a daily fluoride mouthwash (for over 8 years of age) when they can. This will reduce the risk of tooth decay as much as possible.
- If you suspect your child may have an oral infection, contact your child’s oncology team and dentist immediately. Make sure your child takes any medicines prescribed by their doctor.
Oral infections can be viral (cold sore – herpes simplex virus), fungal (oral candidiasis) or bacterial (due to an infected tooth). Infections will tend to be more aggressive and last for a long time.



How can I help to reduce the dryness inside my child’s mouth?
Dry mouth is also called xerostomia.
Chemo and radiotherapy can affect salivary glands inside the mouth which means less saliva (spit) and thicker saliva. This can make the mouth dry and sore and eating and speaking uncomfortable. Sometimes children’s sense of taste can change. Less saliva to wash away food can also make children more at risk of getting tooth decay.
Drinking plenty of water can help relieve a dry mouth. Older children can use sugar-free chewing gum to increase saliva flow.
Vaseline or emollients can help to protect dry lips and soft tissues.
Moisturising mouth gel applied on the tongue and around the inside of the cheeks can help lubricate the mouth. This can be prescribed by your doctor or dentist.

For children over 8 years old using a daily fluoride mouthrinse (0.05% w/v 230 ppm ) regularly will provide some additional protection for teeth, especially after drinking or eating sugar-containing foods. These can be bought over the counter or prescribed by your child’s doctor or dentist.



Be aware
A dry mouth can persist after cancer treatment is finished. This means that your child is more at risk of developing tooth decay.
How can I help to make my child more comfortable if they have a sore ulcerated mouth?
A sore ulcerated mouth is also called mucositis.
Children can suffer from ulceration during cancer treatment. This can be at any time during treatment depending on which chemotherapy your child is receiving. Their mouth can be sore and eating, drinking and toothbrushing can be uncomfortable.
It is important to keep their mouth clean during this time. Your child’s medical team can prescribe medicine to reduce the soreness.
- A soft toothbrush with a small head will be gentler in a sore mouth. Avoid hard, spicy foods, and strongly flavoured toothpaste which can sting.
- If your child cannot brush their teeth because of the ulcers in their mouth, you can use a diluted chlorohexidine mouth rinse. You can apply this with a fabric swab or sponge. This can help to prevent gum infection.
Chlorohexidine can cause staining of teeth which can be easily removed by your child’s dentist once they are better.
- Unflavoured and non-foaming toothpastes can be helpful in a dry, sore mouth or if children have sensory difficulties.

- Protective mouth gel (Gelclair) creates a coating over the lining in the mouth and throat which provides pain relief and enables children to eat more comfortably.
- Oral gel or lubricants (Vaseline or emollients) can protect the lips and soft tissues and relieve soreness.
- Local anaesthetic mouthwash or spray (Difflam) can be prescribed by your child’s dentist or doctor to reduce soreness especially when children are eating.
- For children over 8 years old using a daily fluoride mouthrinse (0.05% w/v 230 ppm ) regularly if brushing is not possible will provide some protection for teeth and especially after drinking or eating sugar containing foods.
Will the cancer treatment affect the adult teeth that are starting to form?
The adult teeth that are starting to form around the time that your child is having cancer treatment may be affected. This is more common when the treatment begins before the age of seven.
Teeth can:
- have enamel defects (poorer quality tooth mineral)
- be smaller
- have shorter roots
- fail to form (missing adult teeth).
These conditions can increase the risk of your child getting tooth decay or developing dental problems.
The teeth that form after the cancer treatment has stopped are unlikely to be affected.
What do enamel defects look like?

The mineral surface (enamel) of a tooth can have permanent yellow-white-brown patches. These are likely to be caused by treatment upsetting the cells that form enamel. Once children have finished treatment and are well the cells recover and form unaffected enamel.
Can I stop this from happening to my child’s teeth?
Unfortunately, once teeth have an enamel defect it cannot be reversed. So, it is very important for your child to see the dentist more regularly as these teeth can be sensitive and are at higher risk of wearing and developing tooth decay.
Is there anything at home we can do to help protect these teeth?
Sensitive toothpaste such as Pronamel or Sensodyne, can help to reduce sensitivity. They can also use GC Tooth Mousse (not suitable for children with milk protein intolerances or allergies) after brushing at bedtime to protect teeth.


Eating and drinking less acid-containing foods and drinks can reduce the risk of wearing away weaker teeth. These include fruit juice and fruits. Ideally these should be eaten or drunk at mealtimes rather than between meals.
A dentist can also place concentrated fluoride varnish and a protective plastic coating (fissure sealant) on children’s back teeth to protect them from tooth decay, wearing and sensitivity.
If children are worried about the appearance of their front teeth, they can have treatment to help this as they grow older.
How can I reduce my child’s risk of getting tooth decay?
While your child is being treated for cancer, and after the treatment stops, it is always important to look after their dental health. If tooth decay is not treated it can lead to your child:
- developing a severe infection which could put their health at risk
- having pain and swelling
- affect their eating, speaking and smiling
- missing days at school.
Make sure your child is registered with a dentist and has their first dental visit by the time they are one year old. It is important for your child to go for regular dental check-ups at least every six months. NHS dental treatment is free for children.
What is the best way to clean my child’s teeth?
Start brushing your child’s teeth as soon as the first baby tooth comes through (usually six months of age).
- Use a toothbrush with a small head.
- Brush the gum line and every part of the tooth.
- Try to brush teeth twice a day, at bedtime and one other time, for at least two minutes with 1350-1500 parts per million (ppm) fluoride toothpaste.
- Spit out toothpaste after brushing. Do not rinse. This leaves a protective layer of fluoride over their teeth.
- Replace your child’s toothbrush when the bristles are worn (about three months).

- Disclosing tablets show up plaque which helps you brush in the right places. The best time to do this is straight after brushing then brush again for a really good clean.
Do I need to help my child to brush their teeth?
Yes, you do need to support your child’s toothbrushing. Adults will need to help brush teeth for children less than seven years of age.
What toothpaste should I use to provide the maximum protection for my child’s teeth?
As your child is at higher risk of getting tooth decay you should use fluoride toothpaste with 1350-1500 ppm fluoride in it.
The dose of fluoride will be written on the front or back of the toothpaste packet.

Make sure your child spits out the toothpaste and does not rinse after brushing, so a bit of fluoride is left behind on their teeth. This maximises tooth protection.
How much toothpaste should I use on my child’s toothbrush?
For children aged 0 to three years: smear-sized amount.

For children aged three or more years: a pea-sized amount.

My child does not like the taste or the feeling of toothpaste in their mouth. What can I do?
You can buy unflavoured and non-foaming fluoride toothpaste which they may prefer to regular toothpaste.

I find it impossible to brush my child’s teeth. Is there anything that could make it easier?
Choose a time when they are more relaxed like in the bath. Give them their own toothbrush to hold while you are brushing their teeth or use a brushing app that makes cleaning teeth fun, can all help.
Mobile apps such as Brush DJ app are suitable for all ages.
What is the best diet for preventing tooth decay?
A healthy, balanced diet with food and drink low in sugar will help to reduce your child’s risk of developing tooth decay. Snacks can be Low in sugar and still high in calories so try to opt for snacks whenever possible that will reduce the risk of tooth decay.
Try to only give your child food and drinks low in sugar between mealtimes.
Frequently eating and drinking things high in sugar will increase the risk of your child getting tooth decay. This includes fruit, fruit puree, smoothies and dried fruit, cereal bars, flavoured fromage frais, milkshakes and yoghurt drinks, or adding jam, marmalade, honey or syrup to foods and drinks.
The safest drinks for your child’s teeth between meals are water or plain milk.
Do not put sugary or acidic drinks into your child’s feeding bottle and when your child is six months old, give them a drinking cup rather than a feeding bottle.
When your child is ill give them sugar-free medicine. If they are prescribed liquid medicines by their doctor, ask for them to prescribe a sugar-free syrup.
My child will only drink sugary drinks. What can I do?
Putting water into the fridge or a fun drinking bottle or having a special drinking straw can help to encourage children to drink water.
You can also buy a special drinking bottle called “Air up” bottle to put water in. This bottle tricks your senses into thinking you are drinking a flavoured drink when you are drinking only water.
What savoury foods can I give my child between mealtimes as a snack?
Here are some suggestions for snacks low in sugar:
- Fresh sticks of carots, cucumber or pepper
- Twiglets, poppadums and nuts (but not for under fives)
- Unsweetened and savoury crackers
- Crispbread
- Unsweetened, plain or savoury rice cakes
- Bread rolls
- Pitta bread
- Chapattis
- Buttered toast fingers
- Bread sticks
- Cheese (Babybel, cheese strings, cheese triangles)
- Cottage cheese
- Cheese spread
- Marmite
- Houmous
- Savoury sandwiches (cheese and carrot, tuna and cucumber, chicken and tomato, egg and cress, chicken and sweetcorn, sardine and tomato)
How do I maximise protection for my child’s teeth?
The information below shows you other things that can be used to protect your child’s teeth as they get older.
Age: 0-3 years
Amount of paste on brush: smear.
Fluoride concentration in toothpaste: 1350-1500 ppm.
Use GC Tooth Mousse after brushing at bedtime (not suitable for children with milk protein intolerances / allergies).
Age: 3-7 years
Amount of paste on brush: pea sized.
Fluoride concentration in toothpaste: 1350-1500 ppm.
Use GC Tooth Mousse after brushing at bedtime (not suitable for children with milk protein intolerances / allergies).
Age: 8 years
Amount of paste on brush: pea sized.
Fluoride concentration in toothpaste: 1350-1500 ppm.
Use GC Tooth Mousse after brushing at bedtime (not suitable for children with milk protein intolerances / allergies).
Use a daily fluoride mouthrinse (0.05% w/v 230 ppm) at a different time to brushing teeth, ideally when your child comes in from school or during cancer treatment following the consumption of sugar containing foods and drinks.
Age: 10 years
Amount of paste on brush: pea sized.
Prescribed concentrated fluoride toothpaste: 2800 ppm.
Use GC Tooth Mousse after brushing at bedtime (not suitable for children with milk protein intolerances / allergies).
Use a daily fluoride mouthrinse (0.05% w/v 230 ppm) at a different time to brushing teeth, ideally when your child comes in from school or during cancer treatment following the consumption of sugar containing foods and drinks.
Age: 16 years
Amount of paste on brush: pea sized.
Prescribed concentrated fluoride toothpaste: 5000 ppm.
Use GC Tooth Mousse after brushing at bedtime (not suitable for children with milk protein intolerances / allergies).
Use a daily fluoride mouthrinse (0.05% w/v 230 ppm) at a different time to brushing teeth, ideally when your child comes in from school or during cancer treatment following the consumption of sugar containing foods and drinks.
Your child’s doctor or regular dentist will need to prescribe your child the concentrated toothpastes (2800ppm and 5000ppm).

What are the main things to remember about looking after my child’s teeth?
- Try to brush your child’s teeth at bedtime and one other time during the day, for two minutes, with 1350-1500 ppm fluoride toothpaste.
- Get your child to spit out after brushing their teeth: no rinsing.
- Try to give your child less sugar and only have sugary food and drink at mealtimes.
Where can I find more information and advice?
Find more information about your child’s teeth and how to care for them
Children’s teeth: NHS UK British Society of Paediatric DentistryDisclaimer: we do not endorse any particular brand of product; these are all examples of what has been described
This leaflet is intended for patients receiving care in Brighton & Hove or Haywards Heath.
The information in this leaflet is for guidance purposes only and is in no way intended to replace professional clinical advice by a qualified practitioner.
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