Is putting the thumb in the mouth hurt the child's teeth?

Sucking a finger or a dummy up to the age of two is fine.

But several studies have shown that beyond this, there is a risk that the front teeth can be pushed out, or the side teeth have turned so that they do not capture the upper and lower sets.

A study by the American Dental Association found that about 20 percent of children who suck their thumb after the age of four have an incompatible bite.