Our teeth do not know whether they are growing in a straight or crooked manner – they just grow. If the mouth is crowded, or if there is an obstacle,( in most cases one or more of the teeth) – theteeth tend to push each other. Our teeth tend to move at any age, for a variety of reasons: chewing, speech, tongue pushing, jaw tightening, gingivitis, or teeth grinding during sleep. The result is crooked teeth. Teeth may be straightened at any age, as long as the teeth, gums and bones are healthy. Moving and correcting the position of the teeth are not age-dependent; however, in an adult, the facial bones and jaw structure are already set. Consequently, in order to repair closure problems and to straighten teeth in adults, more than one type of treatment may be required and for a longer period of time.