Modeling Skull-Face Anatomical/Morphological Correspondence for Craniofacial Superimposition-Based Identification

Abstract

Abstract-Craniofacial superimposition (CFS) is a forensic identification technique which studies the anatomical and morphological correspondence between a skull and a face. It involves the process of overlaying a variable number of facial images with the skull. This technique has great potential since nowadays the wide majority of the people have photographs where their faces are clearly visible. In addition, the skull is a bone that hardly degrades under the effect of fire, humidity, temperature changes, etc. Three consecutive stages for the CFS process have been distinguished: the acquisition and processing of the materials; the skull-face overlay; and the decision making. This final stage consists of determining the degree of support for a match based on the previous overlays. The final decision is guided by different criteria depending on the anatomical relations between the skull and the face. In previous approaches, we proposed a framework for automating this stage at different levels taking into consideration all the information and uncertainty sources involved. In this study, we model new anatomical skull-face regions and we tackle the last level of the hierarchical decision support system. For the first time, we present a complete system which provides a final degree of craniofacial correspondence. Furthermore, we validate our system as an automatic identification tool analyzing its capabilities in closed (known information or a potential list of those involved) and open lists (little or no idea at first who may be involved) and comparing its performance with the manual results achieved by experts, obtaining a remarkable performance. The proposed system has been demonstrated to be valid for sortlisting a given data set of initial candidates (in 62,5% of the cases the positive one is ranked in the first position) and to serve as an exclusion method (97,4% and 96% of true negatives in training and test, respectively).

Preliminary Study of Craniofacial Superimposition by Mathematics Programming in a Thai Population

“…This research, which was still a prototype programme that used simple mathematical theories and had some deviations, could be analysed and applied by using the number of overlapping points as indicators and still required working with a mathematical programme that does not have a graphic user interface to support the operator. When compared to the reference research, they used sophisticated mathematical theories to detect important points on the face for analysis (Campomanes-Alvarez et al 2014;Campomanes-Alvarez et al 2018;Gaudio et al 2016). There was a higher cost of operation and could be done in a semi-automatic system to detect important points (Campomanes-Alvarez et al 2014;Campomanes-Alvarez et al 2018).…”

“…When compared to the reference research, they used sophisticated mathematical theories to detect important points on the face for analysis (Campomanes-Alvarez et al 2014;Campomanes-Alvarez et al 2018;Gaudio et al 2016). There was a higher cost of operation and could be done in a semi-automatic system to detect important points (Campomanes-Alvarez et al 2014;Campomanes-Alvarez et al 2018). There are still deviations in the analysis results (Campomanes-Alvarez et al 2014;Campomanes-Alvarez et al 2018;Gaudio et al 2016), that need to be developed in the future.…”

“…There was a higher cost of operation and could be done in a semi-automatic system to detect important points (Campomanes-Alvarez et al 2014;Campomanes-Alvarez et al 2018). There are still deviations in the analysis results (Campomanes-Alvarez et al 2014;Campomanes-Alvarez et al 2018;Gaudio et al 2016), that need to be developed in the future.…”

“…Before taking the photograph, the cranium and mandible parts of the skull were assembled together by a glue tape. That worked as temporomandibular ligament to connected cranium and mandible (Fehrenbach & Herring 2002). In case of decayed alveolar process due to lost of teeth (Mahakkanaukrauh 2013), we used a clay replacement in that part.…”

“…According to the research, the development of craniofacial superimposition is more reliable by applying computer programmes and mathematical principles in many countries. Such research describes the computer programmes used to compare important points on the face (Campomanes-Alvarez et al 2014), the 2D-3D computer-aided nonautomatic superimposition techniques (Campomanes-Alvarez et al 2018) and modeling skull-face correspondence INTRODUCTION Nowadays, the identification of a corpse to confirm death is the most important before leading to the legal process. There are many ways to identify, such as DNA analysis, iris analysis, fingerprints analysis and etc.…”