First molars, mesial incisors, lateral incisors, cuspids, first premolars, second premolars, and second molars that begin to erupt after the age of 6, including wisdom teeth, are not replaced.
Babies start teething at about 6 months of age, and milk teeth erupt completely at about 2 ½ years of age. all of the milk teeth in a child’s mouth before the age of 6 are teeth that will be replaced. at about 6 years of age the first molar, or the sixth age tooth, begins to erupt. At this time, parents can count backward from the middle of the teeth, the sixth tooth is the sixth age tooth, which is the first permanent tooth that will not be replaced.
Generally, around 12 to 13 years old, all the milk teeth are replaced, and at this time, all the teeth will not be replaced. In daily life, you should supervise your children to brush their teeth carefully and maintain good oral hygiene.