The replacement of milk teeth with permanent teeth begins at about the age of six, as a result of the eruption of permanent teeth, which leads to the stage of mixed teething.[7]
The replacement of the upper teeth begins at the following ages:
Central incisors: 7-8 years.
Lateral incisors: 8-9 years.
First molars: 9-11 years.
Canines: 11-12 years.
Second molars: 9-12 years old.
As for the lower teeth:
Central incisors: 6-7 years.
Lateral incisors: 7-8 years.
First molars: 10-12 years.
Canines: 9-11 years.
Second molars: 11-13 years old.
The process of eruption of permanent teeth leads to the resorption of the deciduous teeth, including the roots, to make room for the permanent teeth.
This process lasts 6-12 years, and the permanent teeth are replaced in all the jaws when the person reaches the age of thirteen. The permanent tooth may fail to grow, so the deciduous tooth remains in its place.[7]