Normal Development of Teeth

The first warning 5 to 6 years of age
The first adult molars come in behind the baby other teeth, before any teeth are lost. The adult teeth are developing inside the bone.
Excessive Protrusion of the Upper Front Teeth
The second warning 7 to 8 years of age
The baby front teeth get loose and fall out. Larger adult teeth grow in to replace them. This is the stage where parents often see crowding begin.
A Deep Bite
The third warning 9 to 10 years of age
Baby teeth on the sides of the mouth begin to fall out and larger adult teeth replace them.
An Underbite
The fourth warning 11 to 12 years of age
The tooth replacement process continues. If crowding has not been corrected with Phase I orthodontic treatment prior to this stage, extractions are often needed to prevent the last teeth from being blocked out of the dental arch.
An Open Bite
The fourth warning 13 to 14 years of age
The second molars finish their eruption, completing the adult or permanent dentition.
An Open Bite
The sixth warning Young adult
If there is enough room, the wisdom teeth erupt in young adulthood.
Midlines Don't Match