[Vertical development of the face and cervical spine. Diagnostic and therapeutic significance in orthodontics and maxillofacial surgery].

Vertical growth of the cervical spine, of the mandibula and the upper maxilla are normally anatomically and physiologically correlated. At a very early age the relationships are established between the cervical spine and the angle of the mandibula which is normally level with C2's antero-inferior angle. A parallelism can be noticed between the rhythms of the vertical growth of the cervical spine and the changes of the maxillary in relation to the skull. So relationships are gradually established between the palate level, the top of the odontoid, and the foramen magnum. These relationships are well objectivized on a lateral teleradiography by Delaire' analysis. Lateral teleradiography of the situation of the angle of the mandibula, in relation to the basis of the C2 body should be systematic. It provides much information concerning the growth potential of the condylar unit, and makes possible a differential diagnosis between true or false posterior vertical insufficiency (PVI) and true or false posterior vertical excess (PVE) and to recognize clinical types of skeletal class II and class III of vertical origin.