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Updated: Sep 19, 2025
Author Spotlight: Advancements in 3D Optical Imaging for Comprehensive Body Composition Assessment in Modern Research
Published on: June 7, 2024
Gravity's influence on facial shape changes during vertical and horizontal head scanning: Effects of sex, age, and
Renitta Rajan Thottungal1, Katarína Harnádková2, Ján Dupej1
1Laboratory of 3D Imaging and Analytical Methods, Department of Anthropology and Human Genetics, Faculty of Science, Charles University, Prague, Czech Republic.
Objectives:
Recently, CT scans of the head are increasingly being used for a variety of forensic reasons, regardless of the head position in which the scans were taken. The study is aimed at monitoring differences in facial shape in vertical and horizontal positions caused by gravity. The first aim was to analyze variations in facial morphology due to gravity between sexes, looking into which regions are most affected. The second aim was to understand changes in the facial soft tissue position due to gravity with advancing age. The final objective was to investigate how variations in body fat percentage influence facial changes due to gravity.
Materials And Methods:
The study uses 3D facial scans of 132 Czech and Slovak adults (85 females, 47 males), aged 20-72, captured in vertical and horizontal positions. Differences between both facial polygon networks representing the influence of gravity were analyzed by geometric morphometric methods (CPD-DCA, color-coded maps) and the Morphome3cs II software.
Results:
Both sexes showed a similar but otherwise intense shift of facial soft tissues in horizontal position. Males exhibited a stronger supero-lateral shift from the upper cheek to parotid-masseteric regions, whereas females showed greater buccal retrusion. Intensities of soft tissue displacement in these areas increase with increasing age. Almost the same trend can be observed when comparing soft tissue displacement with normal and increased body fat percentage.
Conclusion:
Positional correction factors should be implemented in craniofacial identification for increased efficiency of facial reconstruction software towards creating realistic approximations.
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