A study on the 3-D standard value of mandible for the diagnosis of facial asymmetry / 대한치과교정학회지

ABSTRACT

For an accurate diagnosis and treatment planning of facial asymmetry, the use of 3-dimensional (3-D) image is indispensable. The purpose of this study was to get standard data for the 3-D analysis of facial asymmetry. Computerized tomography (CT) was taken in the 60 normal occlusion individuals (30 male, 30 female) who did not have any apparent facial asymmetry. The acquired 2D CT DICOM data were input on a computer, and the reformatted 3-D images were created using a 3-D image software. Twenty three measurements were established in order to evaluate asymmetry; 15 linear measurements (6 for ramus length, 1 for condylar neck length, and 8 for mandibular body length) and 8 angular measurements (4 for gonial angle, 2 for frontal ramal inclination, and 2 for lateral ramal inclination). The right and left difference of each measurement was calculated and analyzed. It is suggested that the right and left differences of the measurements obtained from the study could be used as references for the diagnosis of facial asymmetric patients.