[Three dimensional study of facial height]

There is no know scientifically accurate method of determining the correct vertical dimension. By the vertical dimension we mean the distance between the subnasale & the bottom of chin when patients were radiograped in the physiologic rest positions with & without prostheses. The author measured seven selected points in a midsagittal profile plane of 50 patients (26 complete upper & lower denture, 24 complete upper & removable lower partial denture) by the cephalometric methods. The following conclusions were obtained from this study. 1. Vertical dimension was measured 70.03 mm during removal of upper & lower dentures in mouth, 70.18 mm during insertion of upper denture only, 70.83 mm during insertion of lower denture only & 70.88 mm during insertion of upper & lower dentures, therefore mandibular denture alone in mouth has a slightly significant effects. 2. Vertical dimension between male & female from partially/fully edentulous patients was proved 72.15 mm in male & 68.81 mm in female. 3. Anterior-posterior displacement is largely associated with upper lip movement & superior-inferior displacement is generally associated with a function of lower lip & mandibular structure movements. 4. The magnitude of horizontal displacement for all points ranged from 0 to 8.4 mm & vertical displacement for all points ranged from 0 to 12 mm displacement. The maximum horizontal displacement in point II & maximum vertical displacement in point III was measured. 5. Increase in height may be associated with contraction of dental arches; or conversely, reduction of vertical height may be associated with expansion of the dental arches due to muscle tonicity & lip contours.