The aim of the present study is to develop a 3D cephalometric imagine procedure with Nemoceph software, based on the method of Katsumata for the localization of the asymmetries in orthodontic patients. We have changed the location of some anatomical landmarks for 3D used in the Katsumata article and the analysis of the asymmetry for each patient, incorporating the length of the mandibular body and the height of mandibular ramus measurements from the right and the left side of the patient. The location of the tooth points are made on scanned models superimposed on the MPR cuts and the 3D. The diagnosis of facial asymmetry in a patient of 8 years with plagiocephaly is made. The results reveal a marked asymmetry index of orbits, chin and upper incisors; an asymmetry index of porion, anterior nasal spine, permanent upper and lower first molars, condileon and gonion. We only have found values of symmetry in the lower incisors and molars. The ramus and mandibular body measurements show a left ramus 18.5% shorter than the right, which in absolute values is 12.4 mm. The conclusions after several tracings of asymmetric patients is that the asymmetry index published in 2005 by Katsumata tells us how much of asymmetrical is an anatomical point on the right side, with regard to the same point on the left side, but does not give us the information of the compensatory location of the points on the three reference planes.
(Rev Esp Ortod. 2013;43(1):005-012)