Common problems that can be corrected with braces include crossbites, crowding, mismatched midlines, openbite, overbite, protrusion, spacing and underbite.

Crossbite
In a crossbite, the upper teeth sit inside the lower teeth, which may cause misaligned jaw growth, fractured teeth, abnormal tooth wear and jaw joint problems.


Crowding
Crowding occurs when teeth have insufficient room to erupt. This can cause the teeth to be positioned in the wrong place and the wrong angle, resulting in chipped and worn front teeth. It also makes it more difficult to clean and teeth and gums.

Midlines not Matched
Dental midlines that do not match are evident when the two upper front teeth and the two lower front teeth do no line up. This may negatively impact proper jaw and dental function. It is usually caused by the bite being off on one, or both sides.


Openbite
Proper chewing is impacted by an openbite in which the upper and lower front teeth that do not touch or overlap one another. Openbites may be caused by habits such as thumb sucking or tongue thrusting. Overbites cause excessive wear of the contacting teeth, jaw joint problems and a narrow upper jawbone. Correction of severe cases in growing children is easy, requiring the use of a simple appliance. The correction of a severe open bite in an adult may require jaw surgery.


Overbite
In an overbite, the upper front teeth extend out over the lower front teeth. In a severe case this can cause the lower front teeth to traumatize the gums behind the upper front teeth.


Protrusion
Protrusion is characterized by the upper front teeth extending too far in front of the lower teeth. Several causes for this condition exist: excessive spaces between the upper front teeth, crowding between the lower front teeth, or deficient growth of the lower jawbone. Treatment of this condition is directed toward correcting the causitive element.


Spacing
Spacing problems may be caused by missing teeth, a tongue which pushes the teeth outward, small teeth, an improper bite or a very wide jawbone.


Underbite
An underbite can be caused by excessive growth of the lower jawbone or insufficient growth of the upper jawbone. This can result in the lower front teeth being in front of the upper front teeth. Since an underbite is often a growth imbalance, it can become more pronounced as the patient grows.
Orthodontic problems caused by excessive or insufficient jawbone growth are best and usually corrected when the patient is growing. A variety of devices can be used by the orthodontist to change the width of the upper jaw, increase or decrease upper jaw length, or increase lower jaw length. After jaw growth has been corrected, the orthodontist is able to move the teeth into their proper places.