Comparison Analysis of 3D CT and Cephalometrics in Craniofacial Measurements

ABSTRACT

The cephalometry can not always to evaluate accurate the real human skull. The reconstructed 3 dimensional image of CT(Computed Tomogram) is more popular method of human skull evaluation. The purpose of this study was to evaluate the difference between the measurements with the cephalometry and that with the 3 dimensional image of CT. Fifteen patients who visited yeungnam university hospital(from Nov. 1999 to Feb. 2000) underwent computed tomography and cephalometry. The average age was a 32-years-old. We measured the midface height(ANS-N, SE-PNS, ANS-SD), the total face height (Me-N, Me-ANS, ANS-UIE, Me-LIE, Me-ID), the midface horizontal(ANS-PNS, PNS-A, PNS-UIE), and the lower face horizontal(Go-Pog, Go-B, Go-LIE). After the acquisition of measurements using 3 dimensional CT and cephalometry statistical analysis was done with paired t-test(p< 0.05). Measured data of the midface height, the total face height and the midface horizontal showed no difference between the length at the cephalometry and that of reconstructed 3 dimensional image of CT, but the lower face horizontal showed statistically significant difference between the two. Both cephalometry and 3 dimensional CT image were accurate method for the measurement of midface height, total facial height and midface horizontal. However for the measurement of lower face horizontal, 3 dimensional CT seems to be a more accurate and reliable method.