Dr. Catherine Liu
Three-dimensional (3D) facial imaging is useful in numerous clinical applications to record soft tissue surface data, for example in orthogenetic surgery planning and review (Plooij et al., 2009). An increasingly popular technique for routine facial imaging is 3D digital stereo photo grammetry (Artopoulos et al., 2014). Scanify (Fuel 3D®) is a newly released ultralow-cost optical scanning device which combines this technology with photometric stereo imaging. The aim of this study was to validate Scanify for 3D imaging of facial casts. Two facial casts, obtained by recording impressions of two subjects, were marked with anthropometric landmarks (Farkas 1994), then digitised repeatedly using Scanify and a previously validated portable digital stereophotogrammetry device (Vectra H1, Canfield©) (Artopoulos, Rosenberg and Coward, 2015). The 3D images acquired with each device were compared using linear interlandmark measurements and 3D surface analysis software. Comparing images acquired with the two techniques, inter landmark measurements were within 1mm of each other and of corresponding reference values, acquired by digital calipers. The mean overall surface difference was <0.3mm. Significant differences were detected in depth measurements, as illustrated by color maps of surface deviations. Scanify data produced significantly higher registration error when merging multiple images (1mm) compared to Vectra.
