Modification of the angle of the lower third of the face

Determination of vertical dimension of occlusion, by roentgencephalometric method, with the help of the angle of the lower third of the face, has been described in literature. The aim of this study was to modify the angle of the lower third of the face and correlate its determination with reference planes for orientation of casts in the articulators space, to determine mea n value and measures of variability of the modified angle in a random sampl e, and the posibility to use this angle as a control value for establishing the hight of the lower third of the face. On a sample of 131 roentgenogram s in L-L projection, with teeth in maximal intercuspation, points: N, IS47, THA, SNA, SNP, Xi and Pg were traced down. By the use of this points the a ngle of the lower third of the face (angle K) was constructed. The values o f the angle were measured and statistically analyzed. Mean value of the ang le was 48.5 degrees, with standard deviation, of 4.41 and coefficient of va riation 9.09%. The investigated angle can serve as a control value for dete rmination of intermaxillary relationships and should not be accepted as an, strict norm.