Anteroposterior deviations– The discrepancy between a pair of closed jaws is known as an anteroposterior discrepancy or deviation.  An example of such a discrepancy would be an overbite (where the upper teeth are further forward than the lower teeth), or an underbite (where the lower teeth are further forward then the upper teeth). Overcrowding– Overcrowding is a common orthodontic problem.  It occurs when there is an insufficient space for the normal growth and development of adult teeth. Aesthetic issues– A beautiful straight smile may be marred by a single misaligned tooth or several teeth. Talk to your dentist about what your expectations and desires may be if this treatment is right for you.