[Factors in craniomandibular asymmetry: diagnostic principles and therapy]

A craniomandibular structural asymmetry can be congenital or hereditary in nature, or can be acquired from traumatic of infectious events. During growth quantitative and qualitative alterations of the functional loads applied to the bones may modify their developmental pattern and lead to asymmetry: this has been show extensively through animals experiments. On the other hand, occlusal alterations may lead to mandibular displacement in maximum intercuspidation (ICP) and, consequently, to an apparent asymmetry. Therefore a distinction can be drawn among: 1) structural asymmetries; 2) displacement asymmetries; 3) mixed types. The different types of asymmetry may be diagnosed through the integrated analysis of the data from clinical examination, TMJ radiographs, teleradiographs and cephalometric analysis. A system is also presented, that analyzes the symmetry degree through Computer Aided Design. The purpose of treatment and the consequent treatment modalities vary in function of the type of asymmetry and the patient's age. When a mandibular displacement is present, it should be treated independently from the patient's age. However, if structural asymmetry is present, the treatment modalities depend on the patient's age. In the growing individual it is possible to exploit the potential modeling during growth and to modify through orthopedic means the residual growth of the patient. However, in the adult patient structural asymmetry can not be managed any more through conservative orthopedics.