The work of identifying human remains during a forensic investigation can be strenuous when the remains are highly mutilated, decomposed or skeletonized. In such cases where the usual methods of investigation fail, facial reconstruction (also referred to as facial approximation) play an important role in establishing the identity of the remains. The ultimate aim of facial reconstruction in a forensic context, therefore, is to recreate the appearance that best resembles the original face of the deceased, in an effort to stimulate recognition that will eventually contribute to personal identification(Tyrrell et. al., 1997). However, it should be noted that facial reconstruction cannot on its own be used for such positive identification but should instead be employed along with other established techniques such as dental records and DNA analysis. Outside the forensic scenario, it is also applied in the field of archaeology to restore the faces of the past, where exact accuracy is not a priority.
Over the years, several techniques of reconstruction have been developed which are all based on the relationship between the soft facial tissues and the underlying skull. There are currently two basic approaches – two dimensional and three-dimensional types of reconstruction. Both techniques employ either a manual or a computerized technique.
The scientific approach to facial reconstructions began in the late 19th century with measurements of facial thickness from cadavers(Vanezis et. al., 1989). These were later followed by the development of various prominent three-dimensional manual reconstruction techniques including the Anatomical (Russian), Anthropometrical (American) and Combination (Manchester) methods developed by Gersimov (1971), Krogman (1964) and Neav (1984) respectively. These methods involve sculpting the facial tissues over the skull with either clay or plasticine taking into account the information obtained from the skull assessment such as age, sex, height, race, etc. It is a combination of both scientific and artistic skill and hence can have subjective interpretations and is also time-consuming as well. Therefore, with the advent of the 20th century, efforts were made to improve the techniques; and with the advancement in technology, new computer-based techniques emerged that claimed to be quicker, more flexible and most importantly, reproducible.
This paper mainly focuses on the three-dimensional aspect and intends to summarise the evolution of the techniques, discussing both the traditional as well as the newer computer-based. The various methods developed over time for measuring the facial tissue thickness, which is a major part of all reconstruction techniques have also been discussed. These techniques however still have a long way to to go and therefore, the problems arising and their limitations have also been addressed.