The feasibility of measuring three-dimensional facial morphology in children.

OBJECTIVE An investigation to determine the feasibility of measuring soft tissue morphology in children using a three-dimensional laser-scanning device. DESIGN Prospective clinical trial. SETTING AND SAMPLE POPULATION University of Wales, College of Medicine and one secondary school in the South Wales region. Sixty live subjects (30 adults, 30 children) were recruited in the study. EXPERIMENTAL VARIABLES Laser scanned images of the subjects were obtained under a reproducible and controlled environment with two Minolta Vivid 900 (Osaka, Japan) optical laser-scanning devices assembled as a stereo-pair. A set of left and right scanned images was taken for each subject and each scan took an average of 2.5 s. These scanned images were processed and merged to form a composite three-dimensional soft tissue reproduction of the subjects using commercially available reverse modelling software. OUTCOME MEASURE The shell deviations between left and right scan of each patient were recorded and analysed for differences. These differences determined whether the subjects could remain still during the time of the scans. RESULTS The results showed that the mean differences between shell deviations for the adult scans and children scans were 0.25 +/- 0.09 and 0.30 +/- 0.09 mm, respectively. Paired t-tests showed that the mean error between subject groups was 0.05 +/- 0.15 mm indicating that there was no difference between the two subject groups (p = 0.18). CONCLUSION The technique as described is clinically reproducible for children and adults and can be used for studies assessing facial changes due to growth or clinical intervention.