There are several different kinds of bite disorders,and their severity can vary widely from person to person.
One of the bite problems that is most detrimental to facial esthetics is the deep overbite, which is the almost complete overlap of the upper front teeth.The edges of the lower teeth may actually bite into the gum tissue of the upper palate.
Some tooth wear is a natural function of aging.As long as it doesn't change your bite, it isn't a functional problem. Occasionally ,however,tooth wear causes a closed bite,which can be a serious disorder. For example,extreme wear of the tooth structure in the back of the mouth can cause partial disintegration of the lower facial tissue.It can give you an aged appearance as if you have no teeth.This problem can exist even in young people.
In a normal bite,the upper teeth slightly overlap the lower teeth.Across bite results when the opposite occurs:when the lower teeth overlap the upper teeth.It can occur in both the front and back teeth.When a crossbite develops in the front teeth,one result is a protruding chin.
Occasionally,the upper and lower front teeth cannot come together when the back teeth are touching.This condition is commonly referred to as an open bite. Heredity, as well as habits such as tongue thrusting, thumb sucking, and pencil biting,can cause open bites.Although people with open bites aren't always aware of the problem,one telltale symptom is difficulty biting with the front teeth.In addition,open bites cause protrusion of the upper lip,making it difficult for patients with open bites too close their lips over their teeth without straining.
Protruded upper front teeth,often called "buck teeth",can detract from even the best of smiles.In severe cases,protrusion results in facial deformity and an inability to close the lips over the teeth.