Acquired anterior open bite and facial arthromyalgia: possible aetiology.

The development of an anterior open bite in four patients with facial arthromyalgia is described. There were radiological signs of condylar erosion in three of these cases. It is proposed that the pre-senile destructive arthropathy of the temporomandibular joint, seen in a small proportion of patients with facial arthromyalgia, results from lysis of articular cartilage and bone, secondary to an inflammatory process initiated by the local release of neuropeptides. Occlusal changes, including anterior open bite, may occur if the destructive arthropathy is severe and outstrips dentoalveolar compensation.