J Korean Assoc Maxillofac Plast Reconstr Surg.  1999 May;21(2):174-188.

Three dimensional analysis of maxillofacial structure by frontal and lateral cephalogram

• Kwon KY
• Lee SH
• Kwon TG

Abstract

The purpose of this study is to evaluate the precision and accuracy of a three dimensional cephalogram constructed by using the frontal and lateral cephalogram of twelve human dry skulls. After achieving the three dimensional image reconstruction program, we tried to apply this program to two dentofacial deformity patients. 1. Conventional nasion relator in cephalostat was used to reproduce the same head position for the same dry skull. The mean difference of the three dimensional cephalogram for the same dry skull was 0.34+/-0.33mm. Closeness of repeated measures to each skull reveals the precision of this method for the three dimensional cephalogram. 2. Concerning the accuracy, the mean difference between the three dimensional reconstruction data and actual lineal measurements was 1.47+/-1.45mm and the mean magnification ratio was 100.24+/-4.68%. This Diffrerence is attributed mainly to the ill defined cephalometric landmarks, not to the positional change of the dry skull. 3. Cephalometric measurement of lateral and frontal radiographs had no consecutive magnification ratio because of the different focus-object distance. The mean difference between the frontal and lateral cephalogram to the actual lineal measurements was 4.72+/-2.01mm and -5.22+/-3.36mm. Vertical measurements were slightly more accurate than horizontal measurements. 4. Applying to the actual patient analysis, it is recommendable to use this program for analyzing the asymmetry or spatial change after operation. The orthodontic bracket would be a favorable cephalometric landmark for constructing the three dimensional images.

MeSH Terms

Dentofacial Deformities
Head
Humans
Imaging, Three-Dimensional
Orthodontic Brackets
Skull