Photo copyright Giorgio Fiorelli
Posterior crossbite is when the top back teeth bite down inside the bottom back teeth. It occurs when the top teeth or jaw are narrower than the bottom teeth and can happen on one or both sides of the mouth. The condition affects between 1% and 16% of children who only have their baby teeth. Most posterior crossbites (50% to 90%) remain even when the permanent teeth erupt. In a minority of children, the problem self-corrects.
In order to obtain a more comfortable bite, the lower jaw shifts to one side into a position that allows more teeth to come into contact. However, this shifting of the lower jaw may lead to tooth grinding, and this may lead to other dental problems including the tooth surface being worn away, abnormal growth and development of the teeth and jaws, and jaw joint problems.
Therefore, we need to find safe and effective treatments to correct posterior crossbites or expand the top back teeth, or both. One way of doing this is using orthodontic treatments. This can be more effective in children because the two halves of the roof of the mouth have not fully joined yet, so the top back teeth can be expanded more easily. Orthodontic treatments can also be used to treat posterior crossbites in adults, but they are more likely to need surgical treatments, which are not the focus of this review. Continue reading
Cochrane Oral Health 