If you need to know at what age each tooth must come out, here is a guide on the evaluation of dental age starting at 6 years old.
You will notice that dental age does not always match the chronological age. Evolution of dentition can be late or early compared to chronological age and thus, we have to know how to adapt therapeutic decisions to the development of the child or teenager.
Permanent teeth tend to erupt in group and it is as important to know at what age teeth need to erupt as it is to know the most frequent sequence of eruption.
The different phases of eruption are listed in dental age which does not always match the chronological age.
It is very important to know the distinction and adapt therapeutic solutions to dental age and not only to chronological age.
Dental age is determined according to the following characteristics:
- Eruption of the permanent tooth.
- Level of root resorption of the primary tooth.
- State of development of the root of the permanent teeth.
To understand it more easily, follow the slides of the Keynote included in this page.
Dental age 6
Eruption of the lower first molars.
Eruption of the lower central incisors.
Eruption of the upper first molars.
Dental age 7
Eruption of the upper central incisors and the lower lateral incisors.
About half of the roots of the upper lateral incisors are completed.
Canines and premolars will only have their crown completed or will be at the beginning of root formation.
Dental age 8
Eruption of the upper lateral incisors.
There will be a delay of 2-3 years before the eruption of other permanent teeth.
Dental age 9
One third of the roots of the lower canines and first premolars will be completed.
Root development of the lower second premolar barely starts.
Root development of the upper first premolar has started and the crown of the canines and the upper second premolars is completed.
Dental age 10
Development of half of the root of the canines and lower first premolars.
Development of almost half of the root of the upper first premolars.
Significant development of the roots of the upper canines, lower second premolars and upper second premolars.
Roots of the lower incisors are completely formed (closed apex).
Dental age 11
Roots of all incisors and first molars are completed.
Characterized by the eruption of a new group of teeth, the lower canines erupt, followed quickly by the lower first premolars.
In the maxilla, the first premolar starts erupting.
The upper primary canines and the upper and lower primary second molars are the only ones remaining.
Dental age 12
First, the upper canines and the upper and lower second premolars erupt.
Followed by the eruption of the lower second molars before the upper ones.
Dental ages 13, 14, 15
Characterized by root development of the permanent teeth having recently erupted. At 15 years of age, the third molar is forming and the roots of all permanent teeth should be completed.
A child who has an early dental development could have a dental age of 12 for a chronological age of 10 and inversely for a child having a slower development, a dental age of 12 for a chronological age of 14.
It is more important to recognize an anomaly in dental development than a delay or acceleration. For instance, an upper canine that has not erupted at 14 years of age can be considered normal if the second premolar has not yet erupted.
However, if the second premolars have erupted at 12 years of age and the canines are not yet there, maybe there is something wrong.
A few deviations from what is normal having a significant clinical importance should be known or recognized:
1-The eruption of the lower second molar before the lower second premolar.
-decreases space for the second premolar.
2-The eruption of the upper canine before the upper second premolar.
-the canine will erupt more labially, in ectopia.
3-Asymmetry of eruption between the left and right sides.