In a normal bite, the upper teeth sit a little outside the lower teeth at the front and back and on both sides of the mouth. If a few top teeth are growing slightly behind their lower teeth, we call this a crossbite. There are two main types: 1. Anterior crossbite when front upper teeth are sitting behind their lower ones. 2. Posterior crossbite when the back upper teeth are sitting inside the lower teeth. This crossbite may be on both sides (bilateral) or only one side (unilateral).
The effects of a misaligned bite include tooth decay, gum recession, tooth wear and stress on the jaw muscles, which leads to headaches and chronic jaw, neck, shoulder and back pain. There are many different treatment options including fixed or removable expanders, fixed braces and clear aligners can even be used in some cases.
This case was a posterior unilateral crossbite with mandibular shift and class III malocclusion, which meant the lower jaw moved forward and to the left. Fixed braces was the orthodontic treatment option and achieved an excellent result.