Children with protruding teeth cannot close their mouth well because their lips cannot cover the incisors.
The incisors are outward and project downward, leading to the overbite. In addition, these incisors can be very large and sometimes crowded or poorly positioned, resulting in an unsightly appearance of the child's mouth and smile.
What Causes Protruded Teeth, Buck Teeth, Frontal Teeth Tipping Forward by Dr Mike Mew.