A aproximação fisionômica é o método que busca, a partir do crânio, simular a fotografia de um indivíduo quando em vida. Deve ser empregada como último recurso, na busca de desaparecidos, quando não houver possibilidade de aplicação de um método válido de identificação. O objetivo deste estudo foi obter a aproximação fisionômica, a partir de um crânio seco e de tomografia computadorizada multislice de indivíduos vivos, através da função de base radial hermitiana (FBRH). Constituiu-se também em avaliar o resultado da mesma quanto ao reconhecimento. Na primeira etapa do estudo, foi utilizada a imagem escaneada de um crânio seco, de origem desconhecida, com o intuito de avaliar se a quantidade de pontos obtidos seria suficiente para aplicação da FBRH e consequente reconstrução da superfície facial. Na segunda fase, foram utilizadas três tomografias de indivíduos vivos, para análise da semelhança alcançada entre a face escaneada e as aproximações faciais. Nesta etapa, foi aplicada uma associação de diferentes metodologias já publicadas, para reconstrução de uma mesma região da face, a partir de um mesmo crânio. Na última etapa, foram simuladas situações de reconhecimento com familiares e amigos dos indivíduos doadores das tomografias. Observou-se que a metodologia de FBRH pode ser empregada em aproximação fisionômica. Houve reconhecimento positivo nos três sujeitos estudados, sendo que, em dois deles, os resultados foram ainda mais significativos. Desta forma, conclui-se que a metodologia é rápida, objetiva e proporciona o reconhecimento. Esta permite a criação de múltiplas versões de aproximações fisionômicas a partir do mesmo crânio, o que amplia as possibilidades de reconhecimento. Observou-se ainda que a técnica não exige habilidade artística do profissional. / Facial approximation works by building the visual face up from the skull. This method should be performed as last resort, to carry out for missing persons, when there is no other primary identification method avaliable. The purpose of this study was to introduce a new computerized method with hermite radial basis function (HRBF) for facial approximation using dry skull and computed tomography (CT). The same was also evaluated as a result of the recognition. Firstly, a scan of a dry unidentified skull image was used in order to assess if the amount of points would be sufficient for HRBF methodology and subsequent reconstruction of the facial surface. In second, three CT scans of living individuals were used to evaluate the similarity achieved between the real face scanned and facial approximations. An association of different facial structures reconstruction techniques already published for the same region of the face was applied for the same skull. Moreover, some situations from developed facial approximations were simulated, as recognition by a relative or parent, on a face pool-test. Results from the study showed that the purposed methodology can be used for facial approximation. At the three cases a correct approximation identification as one of a few possible matches to the missing person happened. In two of them, the results were consistently better at identifying the correct approximation. In conclusion, the proposed methodology is fast, objective and reaches visual identification. It is possible to perform multiple versions of the same skull, changing the selected data into the system, which maximizes the chances of establishing recognition of the target face. It was also observed that the technique does not need artistic interpretation.

La reconstitution faciale a pour but de restituer le visage d’un individu à partir de la morphologie de son crâne. Cette technique est utilisée en anthropologie médico-légale pour apporter de nouveaux témoignages dans l’identification de restes humains. Les objectifs de thèse sont d’établir une base de données crânio-faciale 3D de Français grâce à l’imagerie médicale, de tester les règles traditionnelles de reconstitution, et de quantifier les corrélations morphologiques entre tissus osseux et cutanés. Des examens hospitaliers par scanner tomodensitométrique (18 – 96 ans ; sexe ratio 1,16:1) ont été traités avec le logiciel TIVMI pour reconstruire avec précision les surfaces osseuses et cutanées. Plus de 200 points de repère ont pu être positionnés sur 500 individus, en suivant un protocole précis (répétabilité et reproductibilité vérifiées). L’extraction de distances Euclidiennes a permis de tester plusieurs règles traditionnelles, et d’étudier la spécificité et la variabilité des épaisseurs de tissus mous. Parallèlement, les coordonnées 3D des points ont été analysées par morphométrie géométrique. Les covariations entre groupes de points osseux et cutanés ont pu être quantifiées, ainsi que les asymétries, allométries, et influences de l’âge et du sexe sur les variations de conformation. Ces résultats ont permis l’élaboration d’une méthode d’estimation de la position des points de repère du visage, et la création (en collaboration avec le LaBRI) d’un module de reconstitution faciale nommé AFA3D. Basé sur le principe de déformation d’un visage synthétique, ce logiciel restitue la forme la plus probable du visage en fonction de la position de 78 points crâniométriques. / Facial approximation aims at the production of a face based on the skull morphology. This technique is performed in forensic anthropology to bring new testimonies in cases of human remains identification. The goals of this research are to establish a database of French skulls and faces in 3D through medical imaging, to test traditional guidelines, and to quantify the morphological correlations between soft and hard tissues. Computed tomography exams, collected in French hospitals (18 – 96 years; sex ratio 1.16:1), were treated with TIVMI software to reconstruct accurately the bone and skin surfaces. More than 200 landmarks have been placed on 500 subjects, following a protocol which repeatability and reproducibility have been checked. The extraction of Euclidian distances allowed testing traditional guidelines, and studying specificity and variability of soft tissue depths. In parallel, the 3D coordinates were analyzed with geometric morphometrics. Covariations between groups of bone landmarks and groups of skin landmarks were quantified, along with asymmetry, allometry, and influences of age and sex on the shape changes. These results allowed for the creation of a method to estimate the position of skin landmarks, and for the development of a facial approximation module in TIVMI, called AFA3D (in collaboration with the LaBRI). Based on the warping of a synthetic face, this software renders the most probable face depending on the position of 78 cranial landmarks.

This doctoral thesis is submitted in the form of scientific publications together with theoretical introduction. The present state of knowledge of facial approximation methods is presented in the introduction. Areas of application, principles of the method and classification of the methods according to medium used are briefly described. Accuracy and limits of the method are further described as they form a base of the research of this thesis. Simultaneous existence of multiple prediction guidelines, of which the accuracy is not known or published, is typical characteristic of the facial approximation method. The aim of this thesis was to assess the accuracy of the particular prediction rules for estimation of position and size of facial parts (eyes, nose, lips), and based on the results to recommend the most accurate and suitable guidelines for middle European population. An assessment of the strength of the association between craniofacial shape and the shape of soft tissues in the profile using geometric morphometric methods, and determination of the extent to which it might be possible to predict the latter from the former were the purpose of the second part of the research. Material for this study consisted of 87 lateral head cephalograms of a recent adult Central European population (52 males...

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In forensic science one frequently has to deal with unidentified skeletonised remains. When conventional methods of identification have proven unsuccessful, forensic facial reconstruction (FFR) may be used, often as a last resort, to assist the process. FFR relies on the relationships between the facial features, subcutaneous soft tissues and underlying bony structure of the skull. The aim of this study was to develop soft tissue thickness (STT) values for South African black females for application to FFR, to compare these values to existing literature or databases, and to test the accuracy and recognisability of reconstructions using these values. It also established whether population-specific STT values are necessary for FRR. Computerised tomography scanning was used to determine average populationspecific STT values at 28 facial landmarks of 154 black females. The Manchester method of facial reconstruction was employed to build faces, for which antemortem photographs were available, on two skulls that were provided by the South African Police Service’s (SAPS) Forensic Science Laboratory. Different data sets of STT values, namely values from this study, two sets of data from American blacks and a South African mixed ancestry group, were used to build four faces for each of the skulls. Two identification sessions were then held. In the first session, 30 observers were asked to select matches from a random group of 20 photographs of black females which included the two actual images. The identification rates calculated for each photograph revealed that the highest rates of a positive match were for the reconstructions based on South African values. In the second session another group of 30 volunteers were asked to match to each photograph the most similar of the four reconstructions made of that particular individual. The reconstructions with STT values from the current (South African) study were selected more often than the other data sets. Although shortcomings do exist, the identification sessions indicated that FFR can be of value. Furthermore, population-specific STT values are important, since skulls reconstructed using these values were selected or identified statistically significantly more often than the others. AFRIKAANS : In forensiese wetenskap het mens dikwels te doen met ongeïdentifiseerde skeletmateriaal. Wanneer die konvensionele metodes van identifikasie onsuksesvol is, mag forensiese gesigsrekonstruksie (FGR) gebruik word, dikwels as `n laaste uitweg, om die proses te help. FGR is afhanklik van die verhouding tussen die gelaatstrekke, subkutane sagte weefsels en onderliggende benige struktuur van die skedel. Die doel van hierdie studie was om sagte weefsel dikte (SWD) waardes vir Suid-Afrikaanse swart vroue te ontwikkel vir gebruik met FGR, om hierdie waardes te vergelyk met bestaande literatuur of databasisse, en die akkuraatheid en herkenbaarheid van rekonstruksies waar hierdie waardes gebruik was te toets. Dit is gedoen ten einde vas te stel of bevolking-spesifieke SWD waardes nodig is vir FGR. Gerekenariseerde tomografie skandering is gebruik om die gemiddelde bevolkingspesifieke SWD waardes op 28 gesigslandmerke van 154 swart vroue te bepaal. Die Manchester metode van gesigsrekonstruksie is gebruik om twee skedels, waarvan antemortem foto’s beskikbaar was en wat voorsien is deur die Suid Afrikaanse Polisie Diens (SAPD) se Forensiese Wetenskap Laboratorium, op te bou. Verskeie data stelle vir SWD waardes, naamlik waardes verkry in hierdie studie, twee stelle Amerikaanse waardes vir swart vroue en `n Suid Afrikaanse groep van gemengde afkoms, is vir hierdie studie gebruik om vier gesigte van elk van die skedels te bou. Twee identifikasie sessies is gehou. In die eerste sessie is 30 deelnemers gevra om passende foto’s uit `n algemene versameling van 20 foto’s van swart vroue te kies. Dit het die twee ware gesigte ingesluit. Die identifikasie waardes wat bereken is vir elke foto het getoon dat die hoogste waardes vir die werklike foto’s verkry is op rekonstruksies gebasseer op Suid-Afrikaanse waardes. In die tweede sessie was `n ander groep van 30 vrywillgers gevra om die mees soortgelyke van die vier rekonstruksies by die foto van die betrokke individu te pas. Die rekonstruksies met SWD waardes van die huidige (Suid Afrikaanse) studie was meer dikwels gekies as die van ander data stelle. Hoewel verskeie tekortkominge bestaan, het die identifikasie sessies getoon dat FGR van waarde kan wees. Verder is bevolking-spesifieke SWD waardes belangrik, aangesien skedels wat opgebou is met hierdie waardes statisties beduidend meer dikwels gekies of geïdentifiseer is as die ander. / Dissertation (MSc)--University of Pretoria, 2010. / Anatomy / unrestricted

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