Decay in very young children is largely caused by sugary liquid staying in contact with the teeth for long periods — and by far the highest-risk time is at night, when saliva flow drops to its lowest and there is nothing to wash it away or neutralise the acid.
That single fact explains most of the advice below, and it is why a bottle at bedtime matters more than almost anything else you will be told.
The habits that cause it
A bottle in bed
Milk, formula and juice all contain sugars. A child falling asleep with a bottle has that liquid pooling around the upper front teeth for hours, at the point in the day when saliva protection is at its weakest. This is the classic cause of early childhood decay, and the pattern it produces — decay on the upper front teeth, hidden by the lip — is recognisable to any dentist.
Water at night is fine. Anything else is not.
Prolonged night feeding once teeth are through
Frequent feeding through the night after teeth have erupted carries the same risk for the same reason. This needs handling sensitively and in the context of your child’s overall feeding, but where it continues well past the first birthday it is worth discussing with your dentist and your paediatrician, and cleaning the teeth afterwards matters.
Sipping cups carried around
A cup of juice or squash carried through the morning delivers acid attack after acid attack, with no recovery time in between. The volume may be small; the exposure is continuous. This is the most common cause in toddlers past the bottle stage.
Grazing
Continuous snacking has the same effect as continuous sipping. It is frequency, not quantity, that determines damage.
Sweetened medicines
Many children’s syrups are sweetened, and a nightly dose over months is a real risk. Ask whether a sugar-free version exists, give it before brushing rather than after, and rinse with water if it is given at night.
Sharing spoons
The bacteria involved in decay are transmitted, commonly from caregiver to child through shared spoons or cleaning a dummy in your own mouth. It is worth avoiding, and it is worth a caregiver with untreated decay having their own teeth attended to.
What to do, by stage
Before teeth appear
Wipe the gums with a soft damp cloth once a day. It removes residue and establishes a routine before there is anything to argue about.
From the first tooth
Brush twice a day with a smear of fluoride toothpaste appropriate to their age — ask us how much for your child. Brush last thing at night. Spit, do not rinse: rinsing washes away the fluoride you have just applied.
Around the first birthday
Move from bottle to open or free-flow cup as advised for your child. Book the first dental visit — see when should a child first visit the dentist.
Toddler years
Water and milk between meals, nothing else. Keep juice, if given at all, to mealtimes and diluted, in a cup rather than a bottle, and finished rather than carried. Keep sweet things to mealtimes, when saliva flow is high.
Keep brushing for them
Children do not have the manual control to brush effectively until around seven or eight. Let them have a go, then do it properly yourself afterwards — see teaching children to brush properly.
The frequency principle, stated plainly
Every time sugar reaches the teeth, acid is produced for a period afterwards and the enamel loses mineral. Between attacks, saliva restores it. Decay happens when attacks come faster than the recovery.
This is why a whole biscuit at the end of lunch is far less damaging than half a biscuit at four separate points in the afternoon. Parents are often told to reduce sugar and find it impossible; reducing the number of separate occasions is both easier and more effective.
Things worth knowing
- Fruit juice is not a safe alternative to squash. It contains sugar and it is acidic.
- Dried fruit is sticky and stays on the teeth. Better at mealtimes.
- Fizzy drinks, including sugar-free ones, are acidic and erode enamel regardless of sugar content.
- Dummies should never be dipped in anything sweet.
- Cheese at the end of a meal helps neutralise acid — a small, easy habit.
What the dentist can add
Fluoride varnish applied at check-ups, at intervals appropriate to your child’s risk. Advice specific to your child rather than general guidance. And early detection of white-spot lesions, which are reversible at that stage — see tooth decay in children and fluoride and children’s teeth.
Frequently asked questions
Is breastfeeding a cause of decay?
Breastfeeding has well-established benefits. Frequent feeding through the night after teeth have erupted, combined with poor cleaning, is associated with decay risk, so the practical answer is to clean the teeth twice daily and discuss any concerns with us rather than to stop feeding.
How much toothpaste should I use?
It depends on age and on fluoride concentration. Bring the tube to your next appointment.
My child refuses to have their teeth brushed.
Very common. Consistency beats perfection, and specific techniques help — ask us to show you rather than struggling alone.
Is bottled or tap water better?
Fluoride content varies by source. Ask us what applies locally.
Get advice specific to your child
General guidance is a starting point; risk varies between children. See our pediatric dentistry page.
To arrange a consultation at our clinic on Abbas El-Akkad in Nasr City, call +20 101 969 7597 or message us on WhatsApp.
