Guide
Losing baby teeth: what happens when
The change of teeth stretches over several years. The normal range is wide — “late” is far more often striking than actually a problem.
The rough order
It usually starts with the lower front teeth, often around age six. At about the same time a new tooth comes through behind the baby molars without any baby tooth falling out: the first permanent molar.
That tooth is often missed precisely because no wobbly tooth announces it. It is vulnerable to decay while it is only partly erupted — a common reason for fissure sealing.
When to ask
- A permanent tooth comes through behind a baby tooth that is still firmly in place.
- A gap stays empty for a strikingly long time.
- A baby tooth is lost early through decay or an accident.
- Your child consistently chews on one side or complains of pressure.
After an early loss it is worth checking whether a space maintainer makes sense, so the neighbouring teeth do not drift into the gap.
Brushing during this phase
In a mixed dentition, teeth of different heights sit side by side. The brush skims over the lower ones — and that is exactly where decay starts.
It helps to brush newly erupting molars deliberately, holding the brush across them, rather than sweeping along the row in the usual motion.
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Last updated on 26 August 2026