Eruption chronology: when each tooth comes in
What you need to know
- Primary teeth come in between 6 months and 2 and a half to 3 years of age, starting with the lower central incisors.
- At age 6 the first permanent molar comes in, behind the primary teeth, without replacing any of them.
- From ages 6 to 12, primary and permanent teeth coexist: this is the mixed dentition.
- By around age 12–13 all 28 permanent teeth are in; the third molars, if they come in, appear between ages 17 and 21.
- These are average ages: they vary from person to person.
Permanent teeth: eruption age (years)
| Tooth | Upper | Lower |
|---|---|---|
| Central incisor | 7–8 | 6–7 |
| Lateral incisor | 8–9 | 7–8 |
| Canine | 11–12 | 9–10 |
| First premolar | 10–11 | 10–12 |
| Second premolar | 10–12 | 11–12 |
| First molar | 6–7 | 6–7 |
| Second molar | 12–13 | 11–13 |
| Third molar | 17–21 | 17–21 |
Terms in plain words
EruptionThe tooth's whole journey until it reaches its position in the mouth.
Mixed dentitionThe stage when there are baby teeth and permanent teeth at the same time.
For the exam
Which permanent tooth comes in first?
Show answerHide answer
The first molar (6–7 years), along with the lower central incisors. Tip: “at age 6, the 6”.
Sources
- American Dental Association (MouthHealthy): eruption charts for primary and permanent teeth. View source
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