[Factor analysis of anterior deep bite malocclusions and its significance]

A series of 38 measurements was derived from lateral cephalometric radiographs of a large sample of 195 subjects including 130 patients with deep bite malocclusion and 65 control subjects with normal occlusion. These measurements were subjected to a factor analysis which resulted in a series of 8 factors extracted which accounted for 83.3% of the total variance. These factors in rank order of their percentage sample variability were as follows. Factor 1: vertical height; Factor 2: protrusion-retrusion of anterior teeth; Factor 3: protrusion of mid-face; Factor 4: horizontal position of posterior border of the jaws;Factor 5: protrusion of the chin; Factor 6: protrusion of lip; Factor 7: divergence of the face;Factor 8: inclination of upper Lip. The factor scores were further used in a multiple regression analysis in order to predict other cases. The data-reduction method involving a factor analysis would seem to have great significance of clinical application.