ABSTRACT
AIM: The aim of this study is to evaluate the potential of deoxyribonucleic acid (DNA) recovery from bite marks in foods, in different collection types, from DNA quantification. MATERIALS AND METHODS: The sample consisted of 80 swabs, obtained from 20 cheese pieces, bitten by the same person, using the double-swab technique in the center and the periphery of the bite. A statistical analysis was carried out using Statistical Package for the Social Sciences (SPSS) statistical software version 20.0, with values of p < 0.05 being considered statistically significant. RESULTS: The DNA was recovered in all cheese pieces, regardless of the collection types and the bite region. However, the comparative analysis of DNA recovery potential in the four swabs allowed us to infer that the collections in the central region of the bite (DC and WC) were the ones that presented better precision, in addition to extracting a higher DNA concentration, the dry swab being in the center of the bite which presented better results. CONCLUSION: The results proved the effectiveness of the double-swab technique for collecting genetic materials in bite marks; however, in the food used, a single collection at the center of the bite would be enough, optimizing the resources and time needed for the analysis. CLINICAL SIGNIFICANCE: Due to the difficulties of physically comparing a site of a skin lesion and the dental arches of the suspect, the evidence of DNA in saliva has been used to indicate the perpetrator of the bite. In addition, the collection, preservation, and isolation of saliva DNA can be done at low cost and provide flexibility for clinical and laboratory workflow.
Subject(s)
DNA , Food , Forensic Dentistry , Saliva , HumansABSTRACT
Objetivo: O presente trabalho propõe-se analisar a aplicabilidade do método radiográfico de estimativa da idade de Nicodemo, Moraes e Médici Filho (1974), numa população juvenil portuguesa. Material e Métodos: Foi analisada, em 43 panorâmicas, a cronologia da mineralização dos dentes permanentes, segundo o método proposto. A população em estudo corresponde a 43 crianças e adolescentes, 24 do sexo masculino e 19 do sexo feminino, de nacionalidade portuguesa, residentes no distrito de Coimbra e com idades compreendidas entre 6 e 11 anos. Os procedimentos de análise incluíram análise descritiva, pela obtenção de frequências simples e relativas, bem como as medidas de média aritmética e desvio padrão para os intervalos de idade. Resultados:A análise dos resultados obtidos permitiu estimar a idade em 71,0% (31) dos participantes. Quanto ao sexo, observou-se que em 75,0% das panorâmicas analisadas do sexo masculino, a idade cronológica situava-se no intervalo encontrado. No que concerne ao sexo feminino, verificou-se que 68,4% das idades estavam entre os intervalos obtidos. Ao se obter as médias das idades com seus respectivos desvios padrões, observa-se que a idade estimada, compreendida entre 96-108 meses, apresentou-se muito próxima da idade cronológica. Conclusão: Os dados sugerem que a avaliação da estimativa da idade em população portuguesa, por este método, pode auxiliar no processo de identificação. No entanto, faz-se necessário adaptações para esta população, nas idades que foram subestimadas ou superestimadas, além de uma equipe com maior experiência na utilização do método. Descritores: Odontologia forense. Identificação médico-legal. Ortopantomografia.
Subject(s)
Humans , Male , Female , Child , Adolescent , Age Determination by Teeth , Forensic Dentistry , Radiography, Panoramic , Epidemiology, Descriptive , Statistics as TopicABSTRACT
The use of three-dimensional (3D) analysis of forensic evidence is highlighted in comparison with traditional methods. This three-dimensional analysis is based on the registration of the surface from a bitten object. The authors propose to use Cone Beam Computed Tomography (CBCT), which is used in dental practice, in order to study the surface and interior of bitten objects and dental casts of suspects. In this study, CBCT is applied to the analysis of bite marks in foodstuffs, which may be found in a forensic case scenario. 6 different types of foodstuffs were used: chocolate, cheese, apple, chewing gum, pizza and tart (flaky pastry and custard). The food was bitten into and dental casts of the possible suspects were made. The dental casts and bitten objects were registered using an x-ray source and the CBCT equipment iCAT® (Pennsylvania, EUA). The software InVivo5® (Anatomage Inc, EUA) was used to visualize and analyze the tomographic slices and 3D reconstructions of the objects. For each material an estimate of its density was assessed by two methods: HU values and specific gravity. All the used materials were successfully reconstructed as good quality 3D images. The relative densities of the materials in study were compared. Amongst the foodstuffs, the chocolate had the highest density (median value 100.5 HU and 1,36 g/cm(3)), while the pizza showed to have the lowest (median value -775 HU and 0,39 g/cm(3)), on both scales. Through tomographic slices and three-dimensional reconstructions it was possible to perform the metric analysis of the bite marks in all the foodstuffs, except for the pizza. These measurements could also be obtained from the dental casts. The depth of the bite mark was also successfully determined in all the foodstuffs except for the pizza. Cone Beam Computed Tomography has the potential to become an important tool for forensic sciences, namely for the registration and analysis of bite marks in foodstuffs that may be found in a crime scene.
