Sculpting is a way of creating a three-dimensional reconstruction of the head from skeletal remains. It is useful for identification when traditional methods have failed to yield a result. Sculpting is carried out by a forensic artist. The forensic artist first makes a plaster cast of the skull . This is placed on a stand, facing horizontally, so that it can be tilted and turned in all directions as the artist works with it.
The head is built up by placing successive layers of clay on the plaster cast. The artist is guided during the reconstruction by tissue depth data tables. These are compiled from information of how deep a layer of flesh is over various parts of the human skill and how this varies with age, gender, and ethnic origin. Artificial eyes are placed in the eye sockets and hair can be added, either in the form of a wig or as clay layers. The artist may also add various items of clothing as appropriate as aids to identification. Full notes are taken throughout the process and the end product is photographed.
Manual sculpting of a head may take several weeks and is a skilled task. The end result is limited in that the face tends to be devoid of expression. Often, however, it is the expression, or range of expression, on someone's face that is the key to identification. There are now computer programs that can build not just the three-dimensional representation of the face, but also add expression. The program first makes a scan of the skull and then sculpts the face using the same tissue depth tables as the forensic artist. The end result is available much more quickly than it would be by manual processes.
The head can be animated by the computer program by using a virtual head that has simulations of the 24 muscles that control our facial expressions. The head can thus be given various expressions, which may provide additional information that will lead to a positive identification of a skull. If the forensic artist had to do this manually, several trips back to the workbench might be needed to create the different expressions. The program can also show the face with different hairstyles and hair colors. In the future, a computer program may also be developed to add a range of varying skin textures, to make the head come to life to an even greater degree.
see also Composite drawing.