3D Averages in the Study of Differences of Welsh Children

OBJECTIVE: The aim of this study was to evaluate the 3-dimensional facial morphological differences in a cohort of Welsh children.

METHODS: 95 children (53 males and 42 females) with normal facial proportions and an initial mean age of 12.1 years were studied. Laser scanned images were obtained under a reproducible and controlled environment with two Minolta Vivid 900 laser-scanning devices and each child received a set of 3-dimensional scans (comprising a left and right scan). The subjects were further analysed based on whether they did or did not receive treatment (eg: MNT-Males who received no treatment, MT-Males who received treatment, FNT -Females who received no treatment and FT - females who received treatment). Each individual face was obtained as a facial mesh and orientated along a triangulated axis. All faces were overlaid one on top of the other and a complex mathematical algorithm was performed until an average composite face of one male and female was achieved for each sub-grouping

RESULTS: 190 paired scans were obtained and used to create 95 composite faces. The mean differences for the groups MT versus MNT and FT versus FNT were 0.64 ± 0.45mm and 0.32 ± 0.33mm respectively. Furthermore, the mean surface differences for MNT versus FNT were 0.51 ± 0.48mm. Finally, the facial colour maps depicting areas of differences between facial morphologies (brows, nose, nose and lips) were observed in the facial averages studied

CONCLUSIONS: This study demonstrates the effective use of facial averages in the study of children in an epidemiological sample. The results indicate that sub grouping subjects into gender and treatment protocols will aid in the analysis of growth and treatment changes.