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How do permanent teeth replace primary teeth?
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dentistry
The practice of dentistry involves preventing, diagnosing, and treating oral disease, as well as correcting deformities of the jaws, teeth, and oral cavity.
Humans typically develop two sets of teeth during their lifetime: a primary (deciduous) set and a permanent set. The process of replacement occurs as the permanent teeth grow and push toward the mouth cavity.1
As these permanent teeth develop, the roots of the primary teeth are resorbed, which causes the primary teeth to shed. This transition generally begins around age 5 or 6 and is typically completed by age 13.1
It is important to note that not all permanent teeth replace primary ones. While the primary molars are replaced by permanent premolars (bicuspids), the 12 adult molars in the permanent dentition erupt behind the primary teeth and do not replace any of them. This results in a total of 32 teeth in the full adult dentition.1