Investigation into the accuracy and reliability of skull-photo superimposition in a South African sample

One of the aims of forensic science is to determine the identities of victims of crime. In some cases the investigators may have ideas as to the identities of the victims and in these situations, ante mortem photographs of the victims could be used in order to try and establish identity through skull-photo superimposition. The aim of this study was to evaluate the accuracy of a newly developed digital photographic superimposition technique on a South African sample of cadaver photographs and skulls. Forty facial photographs were selected and for each photo, 10 skulls (including the skull corresponding to the photo) were used for superimposition. The investigator did not know which of the 10 skulls corresponded to the photograph in question. The skulls were scanned 3-dimensionally, using a CyberwareTM Model 3030 Colour-3D Scanhead scanner. The photos were also scanned. Superimposition was done in 3D Studio Max and involved a morphological superimposition, whereby a skull is superimposed over the photo and assessed for a morphological match. Superimposition using selected anatomical landmarks was also performed to assess the match. A total of 400 skull-photo superimpositions were carried out using the morphological assessment and another 400 using the anatomical landmarks. In 85% of cases the correct skull was included in the possible matches for a particular photo using morphological assessment. However, in all of these cases, between zero and three other skulls out of 10 possibilities could also match a specific photo. In the landmark based assessment, the correct skull was included in 80% of cases. Once again, however, between one and seven other skulls out of 10 possibilities also matched the photo. This indicates that skull-photo superimposition has limited use in the identification of human skeletal remains, but may be useful as an initial screening tool. Corroborative techniques should also be used in the identification process.The National Research Foundation of South Africa (NRF) and NAVKOM.http://www.elsevier.com/locate/forsciin

Reliability in individual identification by skull-photo superimposition and morphological categorization of face photographs in malaysian males representing the three major races

Skull-photo superimposition is a scientific method for suggesting identification of unidentified human remains. It acquires especial relevance for countries where dental records are not regularly available for identifying the unidentified dead bodies, e.g. India and Southeast Asian countries that includes Malaysia. A research on the reliability of skull-photo superimposition method conducted in 1994 utilizing Caucasoid skulls and face photographs indicated approximately 1 0% possible wrong match. Moreover, the equipments used during that research were those available at that time. The reliability of skull-photo superimposition using Malaysian samples deserved to be studied. In this researc~ a single male skull assessed as Asiatic and 30 face photographs of males, ten each belonging to the three major races in Malaysia, namely Malays, Chinese and Indian, were used. Each male face was represented in two views, frontal and lateral views. Thus, a total number of 60 superimpositions were conducted. The video superimposition device utilized is the state of the art kind which is far advanced compared to the device used during the 1994 research. Furthermore, the relative enlargement of the face photograph was obtained using the distance between Whitnall' s tubercles which assured imposing a condition; it was not done in the earlier research. The superimposed images were examined for the match using the guidelines which included studies of the profile flow in addition to landmark correlations. The result indicated that all the 30 male face photographs could be excluded and there was no wrong match among them. Besides, the traits enabling exclusion were studied. Imposing inter-Whitnall' s tubercular distance as an enlargement parameter indicated non-correlation at the level of the gnathion in 23 of the samples. This is explainable as due to the longer total facial height in the skull. Asymmetry in superimposed images enabled excluding 5 of the samples in which the skull length and face length were comparable. Non-correlation in tissue thickness excluded 2 samples. It is shown that imposing an anatomical parameter for obtaining the face enlargement and application of state of the art equipment and methodology led to increase in the reliability of identification using skull-photo superimposition method. In Malaysia, superimposition-based evidence has been accepted in the courts although the expert was from a foreign country. The fmdings of this research indicate the scope for popularizing skull-photo superimposition as a regular method for identifying the unidentified dead bodies in Malaysia

An investigation into the accuracy and reliability of skull-photo superimposition in a South African sample

One of the aims of forensic sciences is to determine the identities of victims of crime. In some cases the investigators may have ideas as to the identities of the victims and in these situations, ante mortem photographs of the victims could be used and identities established through skull-photo superimposition. The aim of this study was to evaluate the accuracy of a newly developed digital photographic superimposition technique on a South African sample of cadaver photographs and skulls, from the Pretoria Bone Collection. Forty facial photographs were selected and for each photograph, 10 skulls (including the skull corresponding to the photograph) were used for superimposition. The investigator did not know which of the 10 skulls corresponded to the photograph in question. The skulls were scanned 3-dimensionally, using a Cyberware™ Model 3030 Colour-3D Scanhead scanner. Once scanned, the raw data for the skulls were ‘cleaned’ using Cysurf™ programme. The photographs were also scanned for superimposition in the 3D Studio Max programme. Superimposition in 3D Studio Max involves a morphological superimposition, whereby a skull is superimposed over the photograph and assessed for a morphological match. Superimposition using selected anatomical landmarks was also performed to assess the match. A total of 400 skull-photo superimpositions were carried out using the morphological assessment and another 400 using the anatomical landmarks. In 85% of cases the correct skull was included in the possible matches for a particular photograph using morphological assessment. However, in all of these cases, between zero and three other skulls out of 10 possibilities could also match a specific photograph. In the landmark based assessment, the correct skull was included in 80% of cases. Once again, however, between one and seven other skulls out of 10 possibilities also matched the photograph. When using the morphological and landmark assessments combined, 97.5% of correct skulls were included in the list of possibilities, but between one and seven false positives per case were found. This study indicates that skull-photo superimposition has limited use in the identification of human skeletal remains, but may be useful as an initial screening tool. Corroborative techniques should also be used in the identification process.Thesis (PhD)--University of Pretoria, 2011.Anatomyunrestricte

Innovation in prediction planning for anterior open bite correction

This study applies recent advances in 3D virtual imaging for application in the prediction planning of dentofacial deformities. Stereo-photogrammetry has been used to create virtual and physical models, which are creatively combined in planning the surgical correction of anterior open bite. The application of these novel methods is demonstrated through the surgical correction of a case

The virtual human face – superimposing the simultaneously captured 3D photorealistic skin surface of the face on the untextured skin image of the CBCT Scan

The aim of this study was to evaluate the impact of simultaneous capture of the three-dimensional (3D) surface of the face and cone beam computed tomography (CBCT) scan of the skull on the accuracy of their registration and superimposition. 3D facial images were acquired in 14 patients using the Di3d (Dimensional Imaging, UK) imaging system and i-CAT CBCT scanner. One stereophotogrammetry image was captured at the same time as the CBCT and another one hour later. The two stereophotographs were then individually superimposed over the CBCT using VRmesh. Seven patches were isolated on the final merged surfaces. For the whole face and each individual patch; maximum and minimum range of deviation between surfaces, absolute average distance between surfaces, and standard deviation for the 90th percentile of the distance errors were calculated. The superimposition errors of the whole face for both captures revealed statistically significant differences (P=0.00081). The absolute average distances in both separate and simultaneous captures were 0.47mm and 0.27mm, respectively. The level of superimposition accuracy in patches from separate captures ranged between 0.3 and 0.9mm, while that of simultaneous captures was 0.4mm. Simultaneous capture of Di3d and CBCT images significantly improved the accuracy of superimposition of these image modalities

Computer‑aided craniofacial superimposition validation study: the identification of the leaders and participants of the Polish‑Lithuanian January Uprising (1863–1864)

In 2017, a series of human remains corresponding to the executed leaders of the “January Uprising” of 1863–1864 were uncovered at the Upper Castle of Vilnius (Lithuania). During the archeological excavations, 14 inhumation pits with the human remains of 21 individuals were found at the site. The subsequent identification process was carried out, including the analysis and cross-comparison of post-mortem data obtained in situ and in the lab with ante-mortem data obtained from historical archives. In parallel, three anthropologists with diverse backgrounds in craniofacial identification and two students without previous experience attempted to identify 11 of these 21 individuals using the craniofacial superimposition technique. To do this, the five participants had access to 18 3D scanned skulls and 14 photographs of 11 different candidates. The participants faced a cross-comparison problem involving 252 skull-face overlay scenarios. The methodology follows the main agreements of the European project MEPROCS and uses the software Skeleton-ID™. Based on MEPROCS standard, a final decision was provided within a scale, assigning a value in terms of strong, moderate, or limited support to the claim that the skull and the facial image belonged (or not) to the same person for each case. The problem of binary classification, positive/negative, with an identification rate for each participant was revealed. The results obtained in this study make the authors think that both the quality of the materials used and the previous experience of the analyst play a fundamental role when reaching conclusions using the CFS technique.CRUE-CSICSpanish Government Junta de Andalucia CONFIA 2021/C005/00141299 EXAISFI PID2021-122916NB-I00Centro de Investigacion de Galicia "CITIC" - Xunta de Galicia P18-FR-4262European Union (European Regional Development Fund-Galicia 2014-2020 Program)Ministry of Science, ICT & Future Planning, Republic of Korea ED431G 2019/01Universidade da Cor una/CISUG RYC2020-029454-