Permanent teeth in children – when do they come in and how to care for them?

The period when baby teeth are replaced is one of the most dynamic stages in the development of a child’s mouth. It’s the time when small, snow-white baby teeth make way for larger, more durable but also more demanding permanent teeth. As parents, we face the challenge not only of understanding this process – when exactly to expect the first changes and what the tooth eruption timeline looks like – but also of introducing professional, effective hygiene.

When do permanent teeth start coming in? The timeline

Replacing baby teeth is a process spread over time. It usually begins at around 5–6 years of age and lasts into the early teens (around 12–13 years, not counting wisdom teeth). Every child develops at their own pace, but the eruption pattern is usually similar:

1. Sixes (first molars): Often appear first, at around 6 years of age. Note: No baby tooth falls out before them! They come through behind the last baby teeth, which is why parents often miss them.
2. Central incisors: Erupt between 6 and 7 years of age (lower first, then upper).
3. Lateral incisors: Appear at around 7–8 years of age.
4. Premolars (fours and fives): Replace the baby molars between 9 and 12 years of age.
5. Canines and second molars (sevens): Usually come through between 10 and 13 years of age.

Watch out for the “sixes” – teeth that need special care

The first permanent molars, commonly called sixes, are the cornerstone of a healthy bite and among the most important teeth in the mouth. Their role is absolutely crucial: they keep the dental arches stable, enable efficient chewing and influence the proper development of the jaw bones. They erupt at a strategic moment – at around 6 years of age – at the back of the jaws, behind the last baby teeth.

Why are sixes so prone to tooth decay?

1. Surface anatomy: The chewing surface of the sixes is uneven, with many deep grooves and pits. These natural structures help break down food, but they are also perfect traps for bacterial plaque and food debris. Toothbrush bristles often can’t reach the deepest parts of these grooves, which leads to decay developing quickly.
2. Location: Sixes are at the back of the mouth, hard to reach and often hard to see. This makes it difficult for young children, who are still learning precise movements, to brush them thoroughly.
3. Immature enamel: For some time after eruption (up to 2 years), the enamel of a permanent tooth is immature and less mineralised than fully formed enamel. This means it is more vulnerable to acids and decay.

Fissure sealing – a mechanical shield

The most effective way to protect the sixes is fissure sealing. The procedure involves tightly filling the deep grooves and pits with a special light-cured material (sealant).

• Purpose: To smooth the chewing surface of the tooth, removing places where bacterial plaque can collect.
• Procedure: It is painless and quick. The tooth is cleaned, then the sealant is applied to the grooves and hardened with a curing lamp.
• When: Sealing should be done as soon as possible after the six has fully erupted, before decay has a chance to develop. Ask your dentist about regular check-ups and, if needed, renewing the sealant in later years.

Protecting the sixes is an absolute priority that can determine how long your child’s whole set of permanent teeth will last.

Permanent vs. baby teeth – how to tell them apart?

When permanent teeth start appearing in a child’s mouth, their appearance often surprises parents. The new teeth seem bigger, may be uneven and, above all, look less white than the baby teeth before them. This is completely normal and comes from fundamental differences in how the two types of teeth are built.

Differences in colour and structure

The most common cause for concern is the change in colour. Permanent teeth naturally have a more yellowish, sometimes greyish shade compared with baby teeth, which are almost snow-white.

• Dentine thickness: Permanent teeth have a much thicker layer of dentine (the material beneath the enamel), which is naturally yellow. Showing through the enamel, this dentine gives permanent teeth their characteristic darker shade. Baby teeth have thinner dentine and let more light through.
• Enamel mineralisation: Although the enamel of permanent teeth is harder and thicker than that of baby teeth, it is still immature when the tooth erupts. Once fully mineralised, the teeth reach their final colour, but the contrast with the still-white baby teeth can be very noticeable.

Differences in shape and size

Permanent teeth are designed to work for a lifetime, so they need to be bigger, stronger and have a more complex anatomy.

• Mamelons (ridges): Newly erupted permanent incisors often have three small, rounded bumps on the biting edge, called mamelons. They can be worrying, but they are physiological – remnants of how the crown developed. They usually wear down on their own through normal chewing and contact with the opposing teeth within a few months of eruption.
• Crown size: Permanent teeth are simply bigger so they can fill the growing dental arches. At first they may look disproportionately large for a child’s small face, but once all the baby teeth have been replaced and the face keeps growing, the proportions even out naturally.
• Root shape: The roots of permanent teeth are longer, stronger and set at a different angle from those of baby teeth, giving them a permanent, stable anchor in the bone.

Understanding these differences helps parents avoid unnecessary stress and focus on what really matters: giving the new teeth proper protection against decay.

How to care for your child’s permanent teeth? 4 golden rules

While baby teeth are being replaced, hygiene is a challenge. Gums may be swollen, and the gaps left by baby teeth make it easier for food debris to build up.

1. Toothpaste with the right amount of fluoride

Fluoride is a key element in preventing tooth decay, as it supports remineralisation and strengthens the enamel. For children with a full set of permanent teeth or whose baby teeth are being replaced, a toothpaste with 1450 ppm fluoride is recommended. However, make sure your child doesn’t swallow the toothpaste – which is why adults should supervise brushing until around 8–9 years of age.

2. A toothbrush suited to your child’s age

Choosing the right toothbrush is crucial once permanent teeth take over. There are three main types, and the choice should depend on your child’s age, manual skills and individual hygiene needs.

Sonic toothbrushes: Use rapid vibrations (sweeping movements) to create a dynamic cleaning effect that helps remove plaque. Many models have a built-in timer that teaches children to brush for the recommended two minutes. Because they are gentle and very effective, they are very popular while baby teeth are being replaced – although it is essential that the child learns to simply glide the toothbrush over the tooth surfaces rather than scrub.

Manual toothbrushes: Traditional and the simplest to use. They should have a small head that easily reaches the back teeth (especially the hard-to-reach sixes) and soft, flexible bristles. They work well for children who have already mastered the correct brushing technique (sweeping movement), but they need constant parental supervision to be effective.

Electric toothbrushes (rotating/oscillating): Work through fast, rotating movements of the head. They are often recommended for children who find it hard to brush precisely by hand. They deliver a constant number of movements, which increases the chance of removing plaque. However, they need care – pressing too hard can irritate the gums.

3. Flossing is a must

Even the most advanced toothbrush (manual, electric or sonic) can only effectively clean the outer and inner surfaces of the teeth (the cheek and tongue sides) and the chewing surfaces – that is, 3 of the 5 surfaces of each tooth. The other two are the contact points where teeth touch each other.

As permanent teeth come through, physiological crowding is common – the teeth are bigger than the baby teeth before them and sit tightly against each other. Food debris and bacterial plaque collect in these places, out of reach of toothbrush bristles. Neglecting these spaces leads to interproximal decay, which is hard to spot early and often needs dental treatment.

When to start? Flossing becomes essential as soon as the permanent teeth start to sit tightly against each other.

4. A diet for a healthy smile

Even the most meticulous hygiene won’t fully protect permanent teeth if your child’s diet encourages tooth decay. The key is to understand that it’s not only the amount of sugar that matters, but above all how often it is eaten.

Sugar and acidity (pH): Plaque bacteria feed on simple sugars. As they digest them, they produce acids that sharply lower the pH in the mouth (below 5.5), leading to demineralisation (weakening) of the enamel. Permanent teeth, especially just after they erupt, are particularly sensitive to acid attacks.

The “saliva break” rule: Saliva acts as a natural buffer – it is rich in minerals (calcium, phosphorus) and is alkaline, so it can neutralise harmful acids and start remineralising (repairing) the enamel. This repair process takes about 20–30 minutes after a meal. If your child snacks constantly or sips sweet drinks between main meals, the pH stays low all the time and saliva has no chance to do its job.

When should you see an orthodontist?

The period when baby teeth are being replaced is the ideal time for a first visit to an orthodontist (recommended at around 7 years of age). The specialist can assess the growth potential of the jaws, diagnose bite problems at an early stage and check whether the permanent teeth that are about to erupt will have enough room in the dental arch. Early orthodontic treatment (interceptive treatment), often with simple removable appliances, can correct minor problems and avoid the need for complex, lengthy treatment with fixed braces later on.

This stage is the best time for an orthodontic consultation. If you notice that:

• permanent teeth are growing crooked or “in a second row”,
• your child breathes through their mouth,
• there is visible facial asymmetry – don’t put off the visit. Early treatment can prevent complicated treatment in the future.

Summary

Healthy permanent teeth are an investment for life. Good hygiene, regular check-ups and the right oral care products are the foundations that you – the parent – build.

Looking for proven oral hygiene products for your child? Check out our range of sonic toothbrushes and dentist-recommended toothpastes at ApkoStore.com. Take care of your child’s smile the professional way!