earticle

영어

This study is to show the qualitative analytic methods of facial asymmetry with threedimensional
morphometry and find out asymmetry change resulted from enlarging three local regions.
Steel balls (1.2 in diameter) were attached in twenty seven landmarks of a symmetrical
artificial human skull. This artificial human skull was used as experimental materials. Twelve
different asymmetrical artificial human skulls were formed by gradually enlarging the mandibular
body length, gonial angle, and ramus height of the left hemiface.
From the three-dimensional morphometry of each skull type, nine local area measurements and
three total sum area measurements(representing the mandibular area, maxillary area, and lower
facial area) were acquired and made into the surface area asymmetry degree. Menton deviation
itself was used as the surface area asymmetry degree while right-left percentages were used in the other measurements. These surface area asymmetry degrees were compared with each other to find out asymmetry change according to the degree of actual facial asymmetry. Through the statistical analysis, following results were obtained.
The results were as follows:
1. Left maxillary area of artificial human skull was 7.13 0.26% larger while mandibular area
was 4.14 0.12% smaller than each those of right hemiface. After all, left lower facial area
was 1.44 0.07% larger than those of right hemiface.(n=7)
2. Among the reduce rates of surface area asymmetry degree resulted from enlarging three local
regions, ramus height was similar to mandibular body length while it was bigger than those of
gonial angle.
3. Among the increase rates of menton deviation resulted from enlarging the local regions, ramus
height was the biggest, mandibular body length was the second and gonial angle was the
smallest.
These results suggest that three-dimensional morphometry can be used to qualitatively analyse
facial asymmetry and the asymmetry degree is more influenced by enlarging the ramus height,
mandibular body length than those of gonial angle.