Types of Facial Reconstruction
Facial reconstruction is a method of recreating the face of an individual from their skeletal remains. The process involves the combination of the osteology, anatomy, anthropology and artistry methods.
Facial reconstruction is usually used in the field of archaeology and forensic identification. In archaeology, it is used to create three-dimensional visual images of the people from the past, skeletal remains, mummified bodies or bodies kept in bogs. In the context of forensic science, facial reconstruction is used for the purpose of establishing the identity of the deceased whose skeletal remains or mummified body is found.
History of Facial Reconstruction
The first three-dimensional facial approximation from cranial remains was done by Hermann Welcker in 1883 and Wilhelm His Sr in 1895.
In 1964, Mikhail Gerasimov was probably the first to attempt paleo-anthropological facial reconstruction to estimate the appearance of ancient people. Wilton M. Krogmann was the one who popularized facial reconstruction in the field of forensic science.
In 2004, Dr Andrew Nelson of the University of Western Ontario, Department of Anthropology, noted a Canadian artist named Christian Corbet who created the first facial approximation of a 2200 years old mummy based on the CT and laser scans. The reconstruction is called the Sulman Mummy Project.
Types of Facial Reconstruction
Facial reconstruction is basically performed in two ways- two-dimensional facial reconstruction and three-dimensional facial reconstruction.
1. Two-Dimensional Facial Reconstruction
It was developed by Karen T. Taylor of Austin, Texas in the 1980s. This method uses the soft tissue depth estimate for facial reconstruction. It is based on the antemortem photographs and the skull to be constructed.
Now, with the advancement of technology, softwares like CARES (Computer Assisted Recovery Enhancement System) and FACES (Forensic Anthropology Construction Enhancement System) easily and quickly produce the two-dimensional reconstructs which can be edited and manipulated manually.
2. Three-Dimensional Facial Reconstruction
In this approach the reconstruction can be done on a sculpture made from modelling clay/wax or a high resolution three-dimensional image.
In the manual method, the facial reconstruct is prepared by the soft tissue depth markers. The clay markers are inserted into the holes on the skull cast at strategic points or landmarks. The various manual methods used for skull reconstruction include:
- Anthropometric American Method– It is also known as the tissue depth marker method which was developed by Krogmann in 1946. Fine measurements of the soft tissue depths are obtained by the short needles, X-rays and ultrasound. This method is not practiced at present because it requires highly skilled personnel.
- Anatomical Russian Method– Gerasimov developed this method in 1971. It is based on the anatomical arrangement of facial muscles rather than the soft tissues. The facial muscles, glands and cartilages are constructed on the skull cast layer-by-layer. It is much slower than the tissue depth method and requires thorough knowledge of muscle anatomy, therefore is not in use nowadays.
- Combination Manchester Method/ British Method– It is the most accepted method of facial reconstruction today, developed by Neave in 1977. In this method both the tissue thickness and facial muscles are considered for the facial reconstruction. Facial tissue markers (pegs) are inserted in the holes on the skull and muscles of mastication and facial expressions are constructed by the modelling clay. Facial tissue depth is determined by the age, sex, build, etc. of the individual whereas the muscle shape and size is determined on the basis of underlying hard tissues.
These two types of facial reconstruction is done either by computerized method or manually.
Computer Based Reconstruction
Computer software produces reconstruction based on the scanned and stocked photographs. It is a cost effective, fast and efficient method of facial reconstruction which uses three-dimensional computerized models based on clay modelling.
Softwares like ‘Free From Modelling Plus’, ‘Sensable Technologies, Wilmington MA’, are used to model the face on the skull while ‘Phantom Desktop Haptic Device’ uses a virtual sculpture system with Haptic feedback. Haptic feedback system has the ability to feel the surface of the skull during analysis and also provide important skeletal details for facial reconstruction such as muscle attachment strength, position of eye, position of malar tubercle, etc.
It is also used sometimes for facial reconstruction but it is not always included because the investigator already has some knowledge regarding the skeletal remains.
Facial reconstruction is a very helpful anthropological method for determining the identity of an individual but it also has certain limitations like:
- The data regarding tissue thickness is always insufficient.
- Lack of methodical standardization in approximate facial features like eyes, nose, hairstyle, ears, etc.
- Facial reconstruction is majorly based on the artistic subjectivity which may lack the quality of differentiating characteristics used in identification.
- The lacking of proper details provided by the witness are a major hindrance for accurate reconstruction
Since it has many drawbacks, therefore, facial superimposition is not considered as an expert testimony according to the Daubert Standard.
In India, the use of Reconstruction is in growing stages. The police of cities like Mumbai, Chennai, etc. are applying facial reconstruction techniques to identify unknown deceased persons. But this technique needs more advances and accuracy to establish its roots in the justice system.