Decay in a toddler rarely looks like the dark hole most adults imagine. It usually begins as a chalky, matte white band hugging the gum on the top front teeth, easy to mistake for plaque or simply missed. Dentists call decay in children under six early childhood caries. It can appear soon after the first teeth come through, and the habits that cause it are well understood, which makes much of it preventable.
The pattern dentists look for
The upper front teeth are usually affected first. When a baby or toddler drinks from a bottle or sippy cup, liquid pools around these teeth, while the tongue tends to cover and protect the lower front teeth. That is why decay limited to the top front teeth, with the bottom ones untouched, is such a recognisable picture.
Left alone, the white band turns yellow, then brown, and the softened enamel starts to crumble. The upper baby molars can follow as they arrive. Children often do not complain until the decay is quite advanced, so the first clue may be a tooth that has chipped or broken.
Lift the lip once a month
A quick home check takes a few seconds. With your child lying back on your lap, gently lift the top lip and look at the front teeth near the gum, ideally in good light. You are looking for dull white lines, brown spots, or any area that looks different from the rest of the tooth. Anything you are not sure about is worth showing a dentist or OHT, because white-spot decay caught at this stage can often be stopped. Our article on reversing early decay explains how.
Frequent sips keep teeth under attack
Every time sugar reaches the teeth, bacteria in plaque turn it into acid for a period afterwards. Saliva gradually neutralises that acid and helps enamel repair. A child who sips sweet drinks on and off through the day, or falls asleep with milk or juice, gives the teeth no recovery time. Overnight is the riskiest period, because saliva flow drops during sleep. Our guide to sugar and tooth decay covers the chemistry in more detail.
Milk and formula contain natural sugars too. They are good foods, but the same frequency rule applies. Fruit juice, cordial, flavoured milk and sweet teas are a bigger problem, especially from a bottle.
The scale of the problem is not small. In the national child oral health study run from 2012 to 2014, about one in four Australian children aged 5 to 10 had untreated decay in their baby teeth.
Habits that protect young teeth, by stage
From the first tooth
Clean the teeth twice a day with a soft infant brush or a clean cloth. Australian guidance is not to use toothpaste before 18 months unless a dentist advises it. Avoid putting your baby to sleep with a bottle of anything other than water, and if a feed is part of settling, try to finish it before the child is asleep.
Around 12 months
Start moving from bottle to an open or free-flow cup. Keep water as the main drink between meals and plain milk with meals. The Australian Dental Association recommends a first dental visit when the first teeth appear, so if your child has not been yet, now is a good time.
Toddler years
From 18 months to 5 years, use a pea-sized amount of low-fluoride children's toothpaste, and encourage spitting out rather than rinsing. Our guide on how much toothpaste children need has the details. Keep sweet foods to mealtimes rather than grazing. At check-ups, fluoride varnish may be painted on to strengthen the enamel, and sealants may be discussed later as the adult molars arrive.
If decay has already started
Finding decay in a toddler is common and is not a reason for guilt. Early white spots may need only fluoride and changed habits. Cavities may be stopped with painted treatments, filled, or covered, depending on the tooth and the child. Our article on whether baby tooth cavities need treating explains the options. Extensive decay in a very young child is sometimes treated by a registered paediatric dentist, occasionally under general anaesthetic.
Questions parents raise
Are night breastfeeds a problem for teeth?
Breastfeeding has many benefits, and frequent night feeds in the first year are normal. Some studies suggest that frequent, prolonged night feeding after about 12 months, combined with other sugars in the diet, is linked with more decay. Gently wiping the teeth after the last feed and keeping other sugars low can help. A dentist or OHT can talk this through without judgement.
Is watered-down juice safe in a bottle?
Diluting juice reduces the sugar per mouthful but not the number of acid attacks, so it is still best kept out of bottles. Water is the safest drink between meals.
A first visit for your little one
Early visits are short, mostly a look in the mouth on a parent's lap, and a chance to ask questions. Our first visit guide explains what happens, and eligible families can use the Child Dental Benefits Schedule. To book, see our current deals page.
This article is general information and not a substitute for an individual dental assessment.
