Roentgenostatics: A practical evaluation of the x-ray headplate

Abstract

In this relatively brief résumé of my extensive study of roentgenostatics, I have tried to demonstrate the insight into many orthodontic problems that is supplied by the headplate. With some of the diagnostic criteria that I have developed, more precise information concerning orthodontic therapy is available. Gnathometry has proved to be the most important part of the headplate analysis, and I believe that it will play the leading role in the future. It completes and often corrects previous diagnostic impressions derived from examination of the patients, casts, and dental radiographs. Used properly, it makes available valuable guides for treatment and an exact cosmetic prognosis. The greatest advantage of gnathometry is the examination of the dentition itself, independent of craniometric considerations. Fundamental errors in interpretation must occur if the details of malocclusion are related to outside craniometric reference lines or points. An example of this is the measurement of the axial inclination or position of the maxillary incisors in relation to the horizontal Frankfort plane or to the nasion-sella plane. Consideration of the individual jaw inclination and the temporomandibular joint position must be made before malpositions of the teeth in the dentition itself are measured and interpreted. Some techniques which ignore this fundamental consideration also disregard the individual natural skull architecture. Faulty interpretations are made which even decades of clinical experience will not prevent. Particularly in Class II, Division 1 and Class III malocclusions, in bimaxillary protrusions, and in problems involving the extraction of premolars, the cephalometric headplate has proved essential at the time for decision. A major challenge still confronts the orthodontist. He must know to what extent he can influence the morphologic symptoms of a malformation with the therapeutic measures that he has under his control. Cephalometrics will undoubtedly help him delineate the limits of his endeavors.