Eruption and shedding timetable
| Tooth | Erupts | Shed |
|---|
| Central incisor | 6–10 months | 6–7 years |
| Lateral incisor | 9–13 months | 7–8 years |
| First molar | 13–19 months | 9–11 years |
| Canine | 16–22 months | 10–12 years |
| Second molar | 25–33 months | 10–12 years |
Ranges vary widely between healthy children, and a few months either side of these figures is not a concern. What does warrant attention is marked asymmetry — the same tooth erupting on one side and not the other after several months — which can indicate an impacted tooth or a supernumerary tooth in the way.
Why they are not disposable
A primary molar is a space maintainer that happens to also chew. Lose one early and the neighbouring teeth drift into the gap within months. The permanent tooth then has nowhere to go and erupts sideways, becomes impacted, or arrives to find the space closed — turning a filling that was declined at age six into
orthodontic treatment at age twelve. This is the single most common way that early neglect becomes expensive later.
- Space maintenance — holding the arch length for the permanent successor.
- Eruption guidance — the resorbing primary root acts as a path for the permanent tooth.
- Chewing and nutrition during the years of fastest growth.
- Speech development — the front teeth are involved in forming several sounds.
- Jaw growth stimulation through normal chewing loads.
Why decay moves faster in a baby tooth
Primary enamel is roughly half the thickness of permanent enamel and the pulp chamber is proportionally much larger. The consequence is that decay reaches the nerve far sooner than a parent expects. A small brown spot on a primary molar is not the early stage that the same spot would represent on an adult tooth. Speed of intervention matters more in children, not less.
An abscess on a primary tooth can damage the permanent tooth forming beneath it. The developing permanent crown sits directly under the primary root, and infection in that area can disturb enamel formation, leaving the adult tooth permanently discoloured or malformed when it eventually erupts. This is the clearest answer to "why treat a tooth that is going to fall out": the tooth being protected is the one underneath.
Practical prevention
- Wipe the gums before any teeth arrive, and brush from the first tooth.
- No bottle in bed. Milk or juice pooling around the upper front teeth overnight produces early childhood caries, sometimes severe by age three.
- Brush for them until around age eight. The manual dexterity for effective brushing arrives later than most parents assume, and supervising is not distrust, it is mechanics.
- Fluoride application and sealants on primary molars, which have deep grooves that a brush cannot enter.
- First dental visit by the first birthday — the value early on is establishing habits and familiarity, so that the first visit is not also the first emergency.
Common questions parents raise
A loose tooth is best left to the child's own wiggling; it will shed when the root has resorbed. A permanent tooth erupting behind a baby tooth that is still firm — often seen with lower incisors — is common and usually resolves, but should be checked if the primary tooth stays solid. A permanent tooth that erupts looking distinctly more yellow than the baby teeth around it is normal, because permanent dentin is thicker and shows through more.
Notes for families based in Korea
Paediatric dental coverage under Korean national insurance applies to enrolled residents; visiting and SOFA-status families generally settle directly, so ask for the itemised estimate up front. If a PCS is approaching, ask for copies of your child's radiographs and a written treatment summary — dental records for children are particularly worth carrying, since eruption timing and prior treatment history inform whatever comes next. We are roughly 30 minutes from Camp Humphreys with English-language consultation. Book a check-up.
Frequently asked questions
Why treat a cavity in a tooth that is going to fall out anyway?
Because of what sits underneath. An untreated cavity can reach the nerve and cause an abscess, and the permanent tooth is developing directly beneath that primary root, so the infection can disturb its enamel formation and leave the adult tooth permanently marked. Beyond that, an early extraction lets neighbouring teeth close the space the permanent tooth needs.
Do baby teeth decay faster than adult teeth?
Yes, considerably. Primary enamel is about half as thick and the pulp chamber is proportionally much larger, so decay reaches the nerve much sooner. A small brown spot on a baby molar represents a more advanced situation than the same spot on an adult tooth would, which is why prompt treatment matters more in children rather than less.
What happens if a baby molar is lost early?
The neighbouring teeth drift into the gap, often within months, and the permanent successor loses the space it needs. It then erupts out of position, becomes impacted, or is blocked entirely, and correcting that later usually means orthodontic treatment. A space maintainer placed after an early loss is a small appliance that prevents a much larger problem.
When should my child first see a dentist?
By the first birthday. The purpose at that stage is not treatment but establishing familiarity and reviewing habits such as bottle use, brushing technique, and fluoride. Children whose first visit happens before anything hurts tend to be far more comfortable with dentistry for life, whereas a first visit that is also an emergency sets an unhelpful pattern.
My child brushes on their own. Is that enough?
Usually not before around age eight. The fine motor control needed to clean the inner surfaces and back molars effectively develops later than most parents expect, so children who brush enthusiastically still miss the areas where decay actually starts. Letting them brush first and then going over it yourself preserves independence while ensuring the job gets done.
My child’s new permanent tooth looks yellower than the baby teeth. Is something wrong?
Almost certainly not. Permanent teeth have thicker dentin, which is naturally yellower and shows through the enamel more, so a new adult tooth beside remaining baby teeth genuinely looks darker by comparison. The contrast fades once the surrounding baby teeth are replaced. A single tooth that is grey rather than yellow is different and should be examined.