The variation in facial tissue depths between sexes, ages, ethnic groups and different nutritional states has been studied over the last 120 years. Facial tissue depth markers are added at the beginning of the facial depiction process and commonly include 15-34 anatomical points on the skull surface. Image provided by Face Lab, Liverpool John Moores University.
Karen Taylor in the USA developed a 2D method involving drawing over a frontal image of the skull. This process included the addition of tissue depth pegs to the skull prior to taking the photographs. Images of the April Lacy case (1982) from Oklahoma City, courtesy of © Karen Taylor.
The ‘manual method’ is a term applied to a depiction process involving materials such as clay or wax applied by a sculptor onto a skull or skull replica. Initially tissue depth pegs are attached to the skull, then the facial muscles are sculpted following anatomical standards and finally soft tissues and skin are added and aged appropriately to create a finished depiction. Image provided by © Ludo Vermeulen.
Laser scanners and clinical imaging (CT, MRI) have allowed practitioners to use non-invasive replication techniques to reduce the damage to human remains. 3D prints can be produced quickly without a messy plaster or silicone casting processes, or a digital reconstruction can be produced using specialist computer software. Portable laser scanners allow practitioners to visit the remains on site rather than transporting them. Image provided by Face Lab, Liverpool John Moores University.
Advances in 3D printing technology has been embraced by practitioners over the past two decades. It is now possible to print a 3D replica of a skull utilising laser scan or clinical image data before the facial depiction process takes place. Alternatively a 3D replica of a finished bust can be printed and then painted, with eyes, wigs and clothing added, if a physical copy of the reconstruction is required. Images provided by PDR Cardiff (www.pdronline.co.uk).
An automated facial depiction from skeletal remains system utilises a 3D laser scan collection of skulls and faces. This system created average faces and skulls for different sexes, ages and ancestry groups and then utilised morphing algorithms to warp the relevant average face to the unidentified skull. Image courtesy of Dr Maria Vanezis (University of Glasgow).
A blind accuracy study, using CT data collected from a living subject, superimposed the facial depiction with the subject’s face (using the skull for alignment) and the contour map represents the differences. Blue represents good accuracy (<2mm) and the largest error (>5mm) is red/orange. 67% of the facial depiction is blue. Image courtesy of Caroline Wilkinson and Chris Rynn, University of Manchester; Myke Taister and Heather Peters, FBI Academy; Stephen Richmond, Cardiff Dental School.
Examples of highly realistic facial depictions created using the 3D manual methods. Left-Right:
- Lady from the Early Middle Ages, the Netherlands © Maja d’Hollosy (www.skullpting.com)
- Tut Ankh Amen © P.Plailly, Elisabeth Daynes (www.daynes.com)
- Phillip II of Macedon © Richard Neave and John Prag (University of Manchester)
- Richard III © Professor Caroline Wilkinson and Janice Aitken (University of Dundee)
Examples of highly realistic facial depictions created using 3D digital methods. Left-Right:
Vienna. XXth International Conference of the Red Cross. Vote during the last plenary session. From 27 September to 9 October 1965.
1965-10 © Fédération / SCHIKOLA, Gustav