Poor Overlap of Teeth

Improper overlap of the front teeth can be in a number of forms:

Excess Overjet

This is when the upper front teeth are too far ahead of the lower front teeth to fit properly. The upper front teeth are usually around 2mm ahead of the lower front teeth. Excess overjet can be due to a mismatch in the growth of the upper and lower jaws. It can also be from a poor oral habit such as sucking on a thumb or fingers or other objects like clothing or blankets. Such a habit will push the upper front teeth forward and the lower front teeth backwards.

Anterior Crossbite

This is when the lower front teeth are ahead of the lower front teeth and it can be due to a mismatch in the growth of the upper and lower jaws. It can also be due to the front teeth growing into the mouth in an unusual angle and once the upper front teeth are caught behind the lower front teeth they will remain that way unless orthodontic treatment is done.

Deep Overbite

This is when the upper and lower front teeth overlap vertically more than normal. The biting edges of the upper and lower front teeth usually overlap vertically approximately 2mm. When the overbite is deeper that this it can cause problems with the overall fit of the bite and it often results in excessive wear of the edges of the lower front teeth.