RESUMO

SUMMARY: The study aims to demonstrate the success of deep learning methods in sex prediction using hyoid bone. The images of people aged 15-94 years who underwent neck Computed Tomography (CT) were retrospectively scanned in the study. The neck CT images of the individuals were cleaned using the RadiAnt DICOM Viewer (version 2023.1) program, leaving only the hyoid bone. A total of 7 images in the anterior, posterior, superior, inferior, right, left, and right-anterior-upward directions were obtained from a patient's cut hyoid bone image. 2170 images were obtained from 310 hyoid bones of males, and 1820 images from 260 hyoid bones of females. 3990 images were completed to 5000 images by data enrichment. The dataset was divided into 80 % for training, 10 % for testing, and another 10 % for validation. It was compared with deep learning models DenseNet121, ResNet152, and VGG19. An accuracy rate of 87 % was achieved in the ResNet152 model and 80.2 % in the VGG19 model. The highest rate among the classified models was 89 % in the DenseNet121 model. This model had a specificity of 0.87, a sensitivity of 0.90, an F1 score of 0.89 in women, a specificity of 0.90, a sensitivity of 0.87, and an F1 score of 0.88 in men. It was observed that sex could be predicted from the hyoid bone using deep learning methods DenseNet121, ResNet152, and VGG19. Thus, a method that had not been tried on this bone before was used. This study also brings us one step closer to strengthening and perfecting the use of technologies, which will reduce the subjectivity of the methods and support the expert in the decision-making process of sex prediction.

El estudio tuvo como objetivo demostrar el éxito de los métodos de aprendizaje profundo en la predicción del sexo utilizando el hueso hioides. En el estudio se escanearon retrospectivamente las imágenes de personas de entre 15 y 94 años que se sometieron a una tomografía computarizada (TC) de cuello. Las imágenes de TC del cuello de los individuos se limpiaron utilizando el programa RadiAnt DICOM Viewer (versión 2023.1), dejando solo el hueso hioides. Se obtuvieron un total de 7 imágenes en las direcciones anterior, posterior, superior, inferior, derecha, izquierda y derecha-anterior-superior a partir de una imagen seccionada del hueso hioides de un paciente. Se obtuvieron 2170 imágenes de 310 huesos hioides de hombres y 1820 imágenes de 260 huesos hioides de mujeres. Se completaron 3990 imágenes a 5000 imágenes mediante enriquecimiento de datos. El conjunto de datos se dividió en un 80 % para entrenamiento, un 10 % para pruebas y otro 10 % para validación. Se comparó con los modelos de aprendizaje profundo DenseNet121, ResNet152 y VGG19. Se logró una tasa de precisión del 87 % en el modelo ResNet152 y del 80,2 % en el modelo VGG19. La tasa más alta entre los modelos clasificados fue del 89 % en el modelo DenseNet121. Este modelo tenía una especificidad de 0,87, una sensibilidad de 0,90, una puntuación F1 de 0,89 en mujeres, una especificidad de 0,90, una sensibilidad de 0,87 y una puntuación F1 de 0,88 en hombres. Se observó que se podía predecir el sexo a partir del hueso hioides utilizando los métodos de aprendizaje profundo DenseNet121, ResNet152 y VGG19. De esta manera, se utilizó un método que no se había probado antes en este hueso. Este estudio también nos acerca un paso más al fortalecimiento y perfeccionamiento del uso de tecnologías, que reducirán la subjetividad de los métodos y apoyarán al experto en el proceso de toma de decisiones de predicción del sexo.

Assuntos

RESUMO

Chile had a violent military coup (1973-1990) that resulted in 3,000 victims declared detained, missing or killed; many are still missing and unidentified. Currently, the Human Rights Unit of the Forensic Medical Service in Chile applies globally recognised forensic anthropological approaches, but many of these methods have not been validated in a Chilean sample. As current research has demonstrated population-specificity with extant methods, the present study aims to validate sex estimation methods in a Chilean population and thereafter establish population-specific equations. A sample of 265 os coxae of known age and sex of adult Chileans from the Santiago Subactual Osteology Collection were analysed. Visual assessment and scoring of the pelvic traits were performed in accordance with the Phenice (1969) and Klales et al. (2012) methods. The accuracy of Phenice (1969) in the Chilean sample was 96.98%, with a sex bias of 7.68%. Klales et al. (2012) achieved 87.17% accuracy with a sex bias of -15.39%. Although both methods showed acceptable classification accuracy, the associated sex bias values are unacceptable in forensic practice. Therefore, six univariate and eight multivariate predictive models were formulated for the Chilean population. The most accurate univariate model was the ventral arc at 96.6%, with a sex bias of 5.2%. Classification accuracy using all traits was 97.0%, with a sex bias of 7.7%. This study provides Chilean practitioners a population-specific morphoscopic standard with associated classification probabilities acceptable to accomplish legal admissibility requirements in human rights and criminal cases specific to the second half of the 20th century.

Assuntos

RESUMO

SUMMARY: Sex identification of a deceased human individual by means of the mandible is very important for forensic dentistry. The aim of the present study was to determine the sex of Chilean individuals by mandible analysis in panoramic radiographies. Linear and angular parameters of the mandible were analyzed from panoramic radiographies (PR). The study included PR of adult Chilean individuals, of both sexes, with optimum solution and contrast, and which allowed the angles and rami of the mandible to be viewed. Sex was determined by univariate and bivariate discriminant function analysis. The sample consisted of 594 PR of individuals aged between 18 and 84 years. The best sex predictor using univariate discriminant function analysis was the mandibular ramus height (MRH) (74.1 %), followed by the distance from the mental foramen - mandibular base (DMF-MB) (69.1 %) and the bicondylar breadth (BC) (66.7 %). The parameters that presented the lowest sex prediction were the angle of the mandible (AM) with 55.0 % and the distance between mental foramina (DMF) with 53.7 %. The best sex prediction was obtained by the step model of discriminant function analysis (80.2 %), including only three parameters: MRH, BC and DMF-MB. The parameters height of the mandibular ramus, bicondylar breadth and distance from the mental foramen - base of the mandible are good predictors of sex in Chilean individuals when used in conjunction; they are therefore indicated for sex determination in the contemporary Chilean population.

La identificación humana de un individuo fallecido a través de la mandíbula es muy relevante para la odontología forense. El objetivo de este estudio fue estimar el sexo de individuos Chilenos a través del análisis de la mandíbula, utilizando radiografías panorámicas. Fueron analizados parámetros lineales y angulares de la mandíbula, a través de radiografías panorámicas (RP). Se incluyeron RP de individuos chilenos adultos, ambos sexos, con solución y contraste óptimos, y que permitían la visualización de los ángulos y ramas de la mandíbula. Se realizó análisis por función discriminante univariada y bivariada para estimación del sexo. Fueron incluidas 594 RP de individuos entre 18 y 84 años. Para el análisis de función discriminante univariado, la altura de la rama mandibular (ARM) fue el parámetro más predictivo (74,1 %), seguido de la distancia foramen mentoniano - base de la mandíbula (DFM-BM) (69,1 %) y el ancho bicondilar (ABCo) (66,7 %). Los parámetros que presentaron menor predicción sexual fueron el ángulo de la mandíbula (AM) con un 55,0 % y la distancia inter-forámenes mentonianos (DIFM), con el 53.7 %. El análisis por pasos fue el modelo de análisis de función discriminante que presentó la mayor predicción sexual (79,5 %), en el cual fueron incluidos sólo tres parámetros: ARM, ABCo y DFM-BM. Los parámetros altura de la rama de la mandíbula, ancho bicondilar y distancia desde el foramen mentoniano hasta la base de la mandíbula son buenos predictores del sexo en individuos Chilenos cuando utilizados en conjunto y están indicados para estimar el sexo en la población chilena contemporánea.

Assuntos

RESUMO

The objective of this study is to assess the performance of an innovative AI-powered tool for sex determination using panoramic radiographs (PR) and to explore factors affecting the performance of the convolutional neural network (CNN). The study involved 207,946 panoramic dental X-rays and their corresponding reports from 15 clinical centers in São Paulo, Brazil. The PRs were acquired with four different devices, and 58% of the patients were female. Data preprocessing included anonymizing the exams, extracting pertinent information from the reports, such as sex, age, type of dentition, and number of missing teeth, and organizing the data into a PostgreSQL database. Two neural network architectures, a standard CNN and a ResNet, were utilized for sex classification, with both undergoing hyperparameter tuning and cross-validation to ensure optimal performance. The CNN model achieved 95.02% accuracy in sex estimation, with image resolution being a significant influencing factor. The ResNet model attained over 86% accuracy in subjects older than 6 years and over 96% in those over 16 years. The algorithm performed better on female images, and the area under the curve (AUC) exceeded 96% for most age groups, except the youngest. Accuracy values were also assessed for different dentition types (deciduous, mixed, and permanent) and missing teeth. This study demonstrates the effectiveness of an AI-driven tool for sex determination using PR and emphasizes the role of image resolution, age, and sex in determining the algorithm's performance.

Assuntos

RESUMO

OBJECTIVE: This study assessed the validity of dimensions in posterior dentition for sex estimation in forensic contexts. DESIGN: A systematic review was established following the Preferred Reporting Items for Systematic Reviews and Meta-Analysis (PRISMA). After assessing the risk of bias and methodological quality with the QUADAS-2 system, the data were subjected to statistical tests for a meta-analysis of diagnostic accuracy and I2 to verify the heterogeneity. RESULTS: The search resulted in 15 studies that underwent qualitative testing, all were selected for quantitative analysis. The papers included: the mesiodistal of the upper first molar, lower first molar, and upper second molar, and the buccolingual of the upper first molar and upper second molar. The results showed that sensitivity and specificity rates were lower with the mesiodistal diameter, with rates of 0.577 for the lower first molar, 0.674 for the upper first molar, and 0.698 for the upper second molar, while the rates were higher with the buccolingual diameter, with 0.724 for the upper first molar, and 0.743 for the upper second molar. The power to estimate sex is greater for males than for females. High heterogeneity was detected among the studies of almost all dimensions, except sensibility for the lower first molar and specificity for the upper second molar. CONCLUSIONS: None of the dimensions reached an accuracy of ≥80%, however, so they are not a reliable method for sex estimation in forensic practice.

Assuntos

RESUMO

SUMMARY: The foramen magnum is an important topographic opening which connects cranial cavity and spinal canal. The analysis of the bone material established that there are differences in the shape of the foramen magnum between individuals. The aim of this study was to determine sex based on shape and size of foramen magnum using geometric morphometrics method. A study was performed on three-dimensional models (3D models) of 214 human skulls of known sex and known age (141 male skulls and 73 female skulls). The skulls are located at the museum of Medical Faculty, University of Sarajevo. Skulls belong to Bosnian population from the mid-twentieth century. All examined skulls were scanned with a laser scanner to obtain their 3D models. On 3D models of the examined skulls, four landmarks were marked on foramen magnum. Analysis of sex determination was performed using the MorphoJ program. Results of this study showed that there are sex differences in the shape and size of the foramen magnum. Sex determination based on the shape and size of the foramen magnum was showed 65.25 % accuracy for male and 63.01 % accuracy for female using geometric morphometrics method. Examination of the effect of size of foramen magnum on sexual dimorphism of shape of foramen magnum showed a statistically significant effect. Sex determination based just on the shape of foramen magnum using geometric morphometrics method was possible with 62.41 % accuracy for male and 58.90 % accuracy for female on examined sample. Sex differences on shape and size of foramen magnum were found using geometric morphometrics method on three-dimensional models of the examined skulls. The percentage of accuracy was higher for male based on the shape and size of the foramen magnum than for female.

El foramen magno es una importante abertura topográfica que conecta la cavidad craneal y el canal espinal. El análisis del material óseo estableció que existen diferencias en la forma del foramen magno entre individuos. El objetivo de este estudio fue determinar el sexo en función de la forma y el tamaño del foramen magno utilizando morfometría geométrica. El estudio se realizó en modelos tridimensionales (modelos 3D) de 214 cráneos humanos de sexo y edad conocidos (141 cráneos masculinos y 73 cráneos femeninos). Los cráneos se encuentran en el museo de la Facultad de Medicina de la Universidad de Sarajevo. Los cráneos pertenecen a población bosnia de mediados del siglo XX. Todos los cráneos examinados fueron escaneados con un escáner láser para obtener sus modelos 3D. En los modelos 3D de los cráneos examinados, se marcaron cuatro puntos de referencia en el foramen magno. El análisis de determinación de sexo se realizó utilizando el programa MorphoJ. Los resultados de este estudio mostraron que existen diferencias de sexo en la forma y el tamaño del foramen magno. La determinación del sexo basada en la forma y el tamaño del foramen magno mostró una precisión del 65,25 % para los hombres y del 63,01 % para las mujeres utilizando morfometría geométrica. El examen del efecto del tamaño del foramen magno sobre el dimorfismo sexual de la forma del foramen magno mostró un efecto estadísticamente significativo. La determinación del sexo basada solo en la forma del foramen magno utilizando morfometría geométrica fue posible con una precisión del 62,41 % para los hombres y del 58,90 % para las mujeres en la muestra examinada. Se encontraron diferencias de sexo en la forma y el tamaño del foramen magno utilizando morfometría geométrica en modelos tridimensionales de los cráneos examinados. El porcentaje de precisión fue mayor para los hombres en función de la forma y el tamaño del foramen magno que para las mujeres.

Assuntos

RESUMO

SUMMARY: Sex estimation is an important aspect of skeletal identification. In addition, previous studies have found that the sex estimation of each race is different. Thus, it is necessary to develop discriminant function equations for the estimation of sex for the Thai population. This study aims to investigate the relationship between width, length and height of the calcaneus and talus with regards to sex and compare the effectiveness of sex estimation between the calcaneus alone, the talus alone, and between both the calcaneus and talus. A total of 200 individuals (100 males and 100 females) were used in this study; ages ranged from 19 to 94 years. Thirteen variables of calcaneus and ten variables of talus were measured. The authors created discriminant function equations for the estimation of sex and tested the efficiency of the equations obtained by using a test group of 40 individuals (20 males and 20 females). By analyzing the mean values of the variables in the calcaneus and the talus, it was shown that males were significantly different from females (p0.05). A stepwise method was used to create 6 equations for sex estimation. The equations were categorized from between the calcaneus alone, the talus alone, and between both the calcaneus and the talus, providing a sex estimation accuracy of between 88.5 and 93.0 %. Using the test group, it was shown that discriminant function equations from the calcaneus alone, the talus alone, and the calcaneus and the talus together, can estimate sex at a high level of accuracy. Sex estimation accuracy was greater than 85 % in all equations. Therefore, the discriminant function equations from the calcaneus alone, the talus alone, and between both the calcaneus and the talus, from this study can be applied to the Thai population.

La estimación del sexo es un aspecto importante de la identificación esquelética. Estudios previos han encontrado que la estimación del sexo de cada raza es diferente. Por lo tanto, es necesario desarrollar ecuaciones de funciones discriminantes para la estimación del sexo de la población tailandesa. Este estudio tuvo como objetivo investigar la relación entre el ancho, el largo y la altura de los huesos calcáneo y talus con respecto al sexo y comparar la efectividad de la estimación del sexo entre el calcáneo solo, el talus solo y entre el calcáneo y el talus. Se utilizaron un total de 200 huesos de individuos adultos (100 hombres y 100 mujeres), cuyas edades oscilaron entre 19 y 94 años. Se midieron trece variables del calcáneo y diez variables del talus. Los autores crearon ecuaciones de funciones discriminantes para la estimación del sexo y probaron la eficiencia de ellas usando un grupo de prueba de huesos de 40 individuos (20 hombres y 20 mujeres). Al analizar los valores medios de las variables en el calcáneo y el talus, se demostró que los huesos de los hombres eran significativamente diferentes al de las mujeres (p0.05). Se utilizó un método paso a paso para crear 6 ecuaciones para la estimación del sexo. Las ecuaciones se clasificaron entre el calcáneo solo, el talus solo y entre el calcáneo y el talus, lo que proporcionó una precisión de estimación del sexo de entre 88,5 y 93,0 %. Usando el grupo de prueba, se demostró que las ecuaciones de funciones discriminantes del calcáneo solo, el talus solo y el calcáneo y el talus juntos pueden estimar el sexo con un alto nivel de precisión. La precisión de la estimación del sexo fue superior al 85 % en todas las ecuaciones. Por lo tanto, las ecuaciones de la función discriminante del calcáneo solo, el talus solo y entre el calcáneo y el talus de este estudio se pueden aplicar a la población tailandesa.

Assuntos

RESUMO

This study sought to provide an up-to-date review of the importance of anatomy to human identification, focusing on the usefulness of anatomical knowledge about the head and neck bones and teeth to sex estimation in routine forensic anthropology methods. A detailed search of osteology applications in forensic sex estimation was conducted through the electronic databases for the 10 years prior to July 2020. Relevant articles and classic literature on the subject were gathered and are outlined in this review. Among the available literature, several metric analyses showed accuracy superior to 80% in sexual diagnosis. Angles measured from the inclination of glabellae and analysis of the external frontal bone surface through three-dimensional computer-aided design emerge as reliable cranial indexes for sex estimation. In the mandible, the condylar and coronoid height, bigonial width, and coronion-gonion distance express significant sexual dimorphism. Measurements of the canine are the best option for sex estimation using teeth, as well as the thickness of the dentine or enamel of incisors. The axis vertebra surpasses other neck bones for sex estimation due to its atypical shape and the presence of the odontoid process. Metric analyses based on anatomy can provide reliable accuracy in sexual diagnosis. Adequate training and anatomical knowledge can reduce bias and interobserver differences, and the use of three-dimensional models and computed tomography images can enhance the accuracy of these methods for sex estimation. However, every method should be validated before being applied to a different population. Key Points• Anatomy-based metric analyses can provide reliable accuracy in forensic sex estimation. • Glabellae inclination, external frontal bone surface, mandible, and canine teeth measurements can reach accuracies superior to 80% in sexual diagnosis.• The use of three-dimensional models and computed tomography images can enhance accuracy in sex estimation.• Every method should be validated before being applied to a different population.

RESUMO

SUMMARY: Sex assessment is an important process in forensic identification. A pelvis is the best skeletal element for identifying sexes due to its sexually dimorphic morphology. This study aimed to compare the accuracy of the visual assessment in dry bones as well as 2D images and to test the accuracy of using a deep convolutional neural network (GoogLeNet) for increasing the performance of a sex determination tool in a Thai population. The total samples consisted of 250 left os coxa that were divided into 200 as a 'training' group (100 females, 100 males) and 50 as a 'test' group. In this study, we observed the auricular area, both hands-on and photographically, for visual assessment and classified the images using GoogLeNet. The intra-inter observer reliabilities were tested for each visual assessment method. Additionally, the validation and test accuracies were 85, 72 percent and 79.5, 60 percent, for dry bone and 2D image methods, respectively. The intra- and inter-observer reliabilities showed moderate agreement (Kappa = 0.54 - 0.67) for both visual assessments. The deep convolutional neural network method showed high accuracy for both validation and test sets (93.33 percent and 88 percent, respectively). Deep learning performed better in classifying sexes from auricular area images than other visual assessment methods. This study suggests that deep learning has advantages in terms of sex classification in Thai samples.

RESUMEN: La evaluación del sexo es un proceso importante en la identificación forense. La pelvis es el mejor elemento esquelético para identificar sexos debido a su morfología sexualmente dimórfica. Este estudio tuvo como objetivo comparar la precisión de la evaluación visual en huesos secos, así como imágenes 2D y probar la precisión del uso de una red neuronal convolucional profunda (GoogLeNet) para aumentar el rendimiento de una herramienta de determinación de sexo en una población tailandesa. Las muestras consistieron en 250 huesos coxales izquierdos, los que fueron dividi- das de la siguiente manera: 200 como un grupo de "entrenamiento" (100 mujeres, 100 hombres) y 50 como un grupo de "prueba". En este estudio, observamos el área auricular, tanto de forma práctica como fotográfica, para una evaluación visual y clasificamos las imágenes utilizando GoogLeNet. Se analizó la confiabilidad intra-interobservador para cada método de evaluación visual. Además, las precisiones de validación y prueba fueron del 85, 72 por ciento y 79,5, 60 por ciento, para los métodos de hueso seco y de imágenes 2D, respectivamente. Las confiabilidades intra e interobservador mostraron un acuerdo moderado (Kappa = 0.54 - 0.67) para ambas evaluaciones visuales. El método de red neuronal convolucional profunda mostró una alta precisión tanto para la validación como para los conjuntos de prueba (93,33 por ciento y 88 por ciento, respectivamente). El aprendizaje se desempeñó mejor en la clasificación de sexos a partir de imágenes del área auricular que otros métodos de evaluación visual. Este estudio sugiere que el aprendizaje profundo tiene ventajas en términos de clasificación por sexo en muestras tailandesas.

Assuntos

RESUMO

SUMMARY: Sex estimation is the first step in human identification. The mandibular ramus and the condyle have been widely used as indicators for sexual diagnosis because they are regions that undergo important morphological changes which increase sexual dimorphism. The object of the present study was to carry out a systematic review to determine the metric parameters of the mandibular ramus that present the greatest sexual dimorphism, and to sex estimation from the angle of mandible (MA). We included documents in English, Spanish and Portuguese which analysed sex estimation or sex diagnosis by metric analysis of the mandibular ramus in humans. The search was conducted in PubMed/MEDLINE, EMBASE, LILACS, up to December 2020. The risks of bias were analysed using the AQUA tool. The search identified 538 studies. After exclusion of duplicates and irrelevant articles, 39 studies were included for qualitative analysis. Of these, 18 studies were carried out on dry mandibles and 21 by imaging techniques, totalling 7270 participants of 14 different nationalities. We found 14 sex-estimation parameters in the mandibular ramus, plus the MA. Sex estimation by the MA is variable; it is a good predictor only for some populations. The height of the mandibular ramus, the angle of mandible, the bicondylar angle and the height of the coronoid process were the estimation parameters cited in the greatest number of studies. The mandibular ramus presents great sexual dimorphism and can be used as a sex predictor in different populations. Although some parameters of the mandibular ramus can present accuracy of almost 80 % when analysed in isolation, more accurate sex estimation is achieved when the parameters are analysed in conjunction.

RESUMEN: La estimación sexual es el primer paso en la identificación humana. La rama mandibular y el cóndilo se han utilizado ampliamente como indicadores para el diagnóstico sexual debido a que son regiones que sufren cambios morfológicos importantes, aumentando el dimorfismo sexual. El objetivo del presente estudio fue realizar una revisión sistemática a fin de determinar los parámetros métricos de la rama mandibular que presentan mayor dimorfismo sexual, bien estimar el sexo a través del ángulo de la mandíbula (AM). Se incluyeron artículos en Inglés, Español y Portugués que analizaron la predicción sexual o el diagnóstico sexual mediante análisis métrico de la rama mandibular en humanos. La búsqueda fue realizada a través de PubMed/MEDLINE, EMBASE, LILACS, con límite hasta Diciembre 2020. El análisis de los riesgos de sesgos se realizó con la herramienta AQUA. Fueron identificados 538 estudios. Tras la exclusión de duplicados y estudios fuera del tema fueron incluidos 39 estudios para análisis cualitativa. De estos, 18 estudios fueron realizados en mandíbulas secas y 21 en exámenes de imagen, totalizando 7270 participantes de 14 nacionalidades distintas. Fueron encontrados 14 parámetros predictores del sexo en la rama mandibular más el AM. La predicción sexual a través del AM es variable, siendo un buen predictor solamente para algunas poblaciones. La altura de la rama mandibular, ángulo bigoníaco, ángulo bicondilar y la altura del proceso coronoides fueron los parámetros predictivos citados en mayor número de estudios. La rama mandibular presenta gran dimorfismo sexual y puede ser utilizada como predictor del sexo en diferentes poblaciones. A pesar que algunos parámetros de la rama mandibular pueden presentar una precisión de casi 80 % cuando analizadas de forma aislada, una mayor predicción sexual es alcanzada cuando los parámetros son analizados en conjunto.

Assuntos

RESUMO

SUMMARY: Sex estimation from fragmentary bone remain is still challenge for forensic pathologist. Ulna has been reported useful for sex estimation by metric analysis. This study generated sex estimation function for fragment and complete of ulnar bone in a Thai population. The function was generated from 200 pairs of ulnar bone, and others 20 pair of ulnar bone were used for test the accuracy of the functions. Olecranon width was the best single variable for sex predicting of proximal part of ulna, which right olecranon width could be classified the sex 90.5 %. While distal end width of ulna was the variable for predicting the sex of distal part, which left distal end width could be classified the sex with 83.0 %. Stepwise discriminant function analysis was applied to proximal part. For proximal part of right ulna 4 measurements were selected (inferior-medial trochlear notch length, olecranon width, olecranon-coronoid process length, and maximum proximal ulnar width), while the left side, superior trochlear notch width, olecranon width, and maximum proximal ulnar width were chosen, and their functions could be predicted the sex with 91.0 % and 90.0 %, respectively. Our results indicated the ulnar bone had high ability for estimating the sex in a Thai population.

RESUMEN: La estimación del sexo a partir de restos óseos fragmentarios sigue siendo un desafío para el patólogo forense. Se ha informado de la utilidad de la ulna para la estimación del sexo mediante análisis métrico. En este estudio se analizó la estimación del sexo para un fragmento y de la ulna completa en una población tailandesa. La función se generó a partir de 200 pares de ulnas y se utilizaron otras 20 pares de ulnas estimando la precisión de las funciones. El ancho del olécranon fue la mejor variable individual para predecir el sexo en la parte proximal de la ulna (90, 5 %). Si bien el ancho del extremo distal de la ulna fue la variable para predecir el sexo, el ancho del extremo distal izquierdo podría clasificarse por sexo con un 83,0 % de certeza. Se aplicó un análisis de función discriminante escalonada a la parte proximal. Para la parte proximal de la ulna derecha se seleccionaron 4 medidas (longitud de la incisura troclear inferior-medial, ancho del olécranon, longitud del proceso olecraneano-proceso coronoides y ancho ulnar proximal máximo), mientras que en el lado izquierdo, fue determinado el ancho de la incisura superior troclear, ancho del olécranon y ancho ulnar proximal máximo. Se eligió el ancho, y se pudo predecir el sexo en el 91,0 % y 90,0 % de los casos, respectivamente. Nuestros resultados indicaron que la ulna tenía una alta capacidad para estimar el sexo en una población tailandesa.

Assuntos

RESUMO

SUMMARY: Although molecular techniques evolved considerably in last years, anthropological methods of assessing skeletal remains, continues to be an important tool in the identification process in medico legal investigations. The objective of this study was to develop a discriminant function equation for estimating sex and stature using several measurements of lumbar vertebrae in a Thai population. We studied 150 lumbar columns (75 male and 75 female) age range of 22 to 89 years from the Forensic Osteology Research Center, Chiang Mai University, Thailand. The quantitative variables with sex were analyzed by the discriminant function analysis and that with stature were calculated using linear regression. The pixel density of the major axis of the trabecular surface of superior endplate of the first lumbar vertebra had the most accuracy in sex determination. The regression equation with quantitative variables in stature estimation described 32.3 % of the total variance with standard error of estimate of 7.736 cm. Lumbar vertebrae can be used as part of the stature and sex quantitatively and qualitatively estimating in Thais incomplete skeletal remains.

RESUMEN: Los métodos antropológicos de evaluación del esqueleto siguen siendo una herramienta importante en el proceso de identificación en las investigaciones médico-legales. El objetivo de este estudio fue desarrollar una ecuación de función discriminante para estimar el sexo y la estatura utilizando varias medidas de las vértebras lumbares en una población tailandesa. Se estudiaron 150 columnas lumbares (75 hombres y 75 mujeres) con un rango etario de 22 a 89 años del Centro de Investigación de Osteología Forense, Universidad de Chiang Mai, Tailandia. Las variables cuantitativas de sexo se analizaron mediante el análisis de función discriminante y la estatura fue calculada mediante regresión lineal. En cuanto a la determinación de sexo, la densidad de píxeles del eje mayor de superficie trabecular de la placa terminal superior de la primera vértebra lumbar fue de mayor precisión. La ecuación de regresión con variables cuantitativas en la estimación de la estatura describió el 32,3 % de la varianza total con el error estándar de estimación de 7,736 cm. Las vértebras lumbares se pueden utilizar como parte de la estatura y el sexo, estimando cuantitativa y cualitativamente los restos esqueléticos incompletos en sujetos tailandeses.

Assuntos

RESUMO

The pelvis and skull are the regions of the human skeleton that most clearly show sexual dimorphism, with the pelvis being superior to the skull for sex estimation owing to reproductive and hormonal factors. However, as many skeletons are found incomplete, it is important to be able to determine sex from analyzing the skull as well as the pelvis. This study was aimed at validating and evaluating the effectiveness of four morphometric methods for sex estimation using the human skull. One hundred human Brazilian skulls belonging to identified but unclaimed skeletons were used after all legal and administrative requirements for exhumation were satisfied. Four dimensions were analyzed: the facial triangle; the bimastoid triangle; the mastoid triangle; and finally, the occipital triangle. These dimensions were used to calculate the triangle areas. Descriptive analysis was used to verify the mean, standard deviation, and confidence interval of all variables and discriminant analysis with cross-validation was used to verify the percentage of correctness of the sex estimation methods. Individual analysis of the areas of the facial, right mastoid, left mastoid, bimastoid, and occipital triangles, and sum of the mastoid triangle areas, produced average accuracies of 63.0%, 81.8%, 77.8%, 71.4%, 64.0%, and 80.8%, respectively. Combinations of triangles resulted in higher mean accuracy percentages, with only 75.6% accuracy recorded when the left and right mastoid triangle areas were removed. All average values of analyzed triangles were higher in males than in females. Analyses of the cranial triangles were useful for sex estimation in the population studied.

Assuntos

RESUMO

The aim is to study the sexual dimorphism of the base of the skull in radiographs of a bone collection of contemporary Colombian adults, with the intention of formulating discriminant functions capable of classifying sex in this population. The sample consisted of 115 skull base radiographs, (44 females and 71 males), which originated from the Colombian Human Skeletals Collection. Radiographs with good contrast were selected. Images of skulls with asymmetries and fractures were excluded. Five measures: Maximum cranial base length, Foramen magnum length, Maximum cranial breadth, Bizygomatic breadth, Foramen magnum breadth length, were preformed using ImageJ5 software ®; an intra-observer error was determined using paired t-test. Statistical analysis showed a sexual dimorphism for all variables (p < 0.05). The step-by-step procedure of the discriminant function selected 2 variables from the 5 (Foramen magnum length and Bizygomatic breadth) and the precision was between 86.4% and 88.6% in the determination of sex. However cross-validation showed an accuracy of 85.7% to male and 87.2% to female. The skull base is highly dimorphic. The established discriminant functions can be used to estimate sex in the Colombian population.

Assuntos

RESUMO

The hip bone (os coxae) is the skeletal element that presents the greatest level of sexual dimorphism. Therefore, methods involving the analysis of the os coxae provide the most accurate sex estimation, and DSP2 (Diagnose Sexuelle Probabiliste v.2) is one of the most accurate tools used in this identification. The goal of this study is to apply and validate DSP2 in the identification of 103 os coxae (53 male and 50 female) belonging to a Brazilian-identified skeletal collection. Differences between sexes were statistically significant for all measurements, except for the acetabulo-symphyseal and spino-auricular lengths. From the 103 os coxae analyzed, there was a 9.43% error in male individuals and a 14% error in females. The results revealed that DSP2 can be applied to Brazilian-mixed populations with a good index of accuracy, although at a lower accuracy than other population samples. This study also clearly demonstrates that metric variation of the os coxae is extremely useful in sex estimation and reinforces the notion that pelvic sexual dimorphism is not population-specific.

Assuntos

RESUMO

Latin American populations are traditionally reported as one ancestral group in the forensic anthropology literature. However, this study illustrates the need for population-specific methodologies for ancestral groups that are considered Latin American. This project evaluated the accuracy of the sex estimation discriminant function created from the tibia of a Mexican population, when applied to a Chilean population. The maximum distal epiphyseal breadth (MDEB) and the anterior-posterior diameter at the nutrient foramen (APDNF) were measured on 203 tibiae (108 males and 95 females) from the Subactual Skeletal Collection at the University of Chile. The individuals ranged in age from 20 to 96 years old. When the Mexican discriminant function was applied to the Chilean population, accuracy rates ranged from 76.0% (males) to 85.0% (females). Mean tibial size comparisons were made to a Mexican, Croatian, White South African, archaeological Hispanic, and North Indian population and showed some significant differences between the variables measured. Population-specific discriminant functions were created for the Chilean population with overall sex classification accuracy rates of 71.4% (MDEB only) to 89.2% (MDEB and APDNF). This study illustrates the need for population-specific and temporally-specific discriminant functions for estimation of sex from the tibia.

Assuntos

RESUMO

This study tests whether postcranial sex estimation methods generated from Hispanic, and mainly Mexican samples, can be successfully applied to other increasingly common migrant populations from Central America. We use a sample of postcranial data from a modern (1980s) Guatemalan Maya sample (n = 219). Results indicate a decrease in classification accuracies for previously established univariate methods when applied to the Guatemalan study sample, specifically for males whose accuracies ranged from 30 to 84%. This bias toward inaccuracies for Guatemalan males is associated with the smaller skeletal sizes for the Guatemalan sample as compared to the samples used in the tested sex estimation methods. In contrast, the tested multivariate discriminant function classification yielded less sex bias and improved classification accuracies ranging from 82 to 89%. Our results highlight which of the tested univariate and multivariate methods reach acceptable levels for accuracy for sex estimation of cases where the region of origin may include Guatemala.

Assuntos

RESUMO

OBJECTIVES: The aim of this study was to test the accuracy of the Klales et al. (2012) equation for sex estimation in contemporary Mexican population. MATERIALS AND METHODS: Our investigation was carried out on a sample of 203 left innominates of identified adult skeletons from the UNAM-Collection and the Santa María Xigui Cemetery, in Central Mexico. The Klales' original equation produces a sex bias in sex estimation against males (86-92% accuracy versus 100% accuracy in females). Based on these results, the Klales et al. (2012) method was recalibrated for a new cutt-of-point for sex estimation in contemporary Mexican populations. RESULTS AND DISCUSSION: The results show cross-validated classification accuracy rates as high as 100% after recalibrating the original logistic regression equation. Recalibration improved classification accuracy and eliminated sex bias. This new formula will improve sex estimation for Mexican contemporary populations.

Assuntos

RESUMO

The scapula is valuable for sex estimation in human skeletons. Muscles provide protection to the scapula making it difficult to fracture, therefore increasing the potential for undamaged scapulae at forensic scenes. The goal of this project is to evaluate the accuracy of discriminant functions, created using an indigenous Guatemalan and contemporary Mexican population, when applied to a contemporary Chilean sample for estimation of sex from the scapula. The length of the glenoid cavity (LGC) and breadth of the glenoid cavity (BGC) were measured. The sample included 114 individuals (58 males and 56 females) with age ranges from 17 to 85years old. When the Guatemalan discriminant functions were applied to the Chilean sample they showed higher accuracy rates for sexing male scapulae (89.6% to 94.8%) than for sexing female scapulae (53.4% to 80.3%). When the Mexican discriminant functions were applied to the Chilean sample they showed higher accuracy rates for sexing female scapulae (82.1% to 96.4%) than for sexing male scapulae (56.9% to 89.6%). Size comparisons were made to a Guatemalan, Mexican, White American, and Greek population. Overall, in males and females of the Chilean population both left and right scapulae were larger than in the Guatemalan population but smaller than in the Mexican, White American, and Greek samples. Population-specific discriminant functions were created for the Chilean population with an overall sex classification accuracy rate of 80.7% to 86.0%.

Assuntos

RESUMO

This research explores the best univariate and multivariate indicators for sex estimation using 51 standard osteometric measurements of all six major postcranial long bones, bones of the shoulder girdle, pelvic girdle, and the calcaneus from a modern, Colombian skeletal collection. The hypotheses being tested are (1) that postcrania will yield accurate sex classification rates and (2) the shoulder girdle will demonstrate the highest discrimination, based on results from previous research. The sample consists of 134 individuals (50 females, 84 males) between the ages of 19 and 93 with a mean age of 47 years. The sample is from the Colombian Skeletal Collection, consisting of skeletons from cemeteries in Bogotá, with recent years of death. The methods include univariate and multivariate discriminant function analysis (DFA). The results for this sample indicate the same general pattern of univariate classification effectiveness as found in research on North Americans; however, here the humerus performs better than the distal femur and proximal tibia as demonstrated in some North American samples. The cross-validated percent correct univariate classification for the postcranial elements ranges from 64.8% to 86.1% (p<0.05). The highest univariate classification rates were for the scapular height (86.1%) and the humeral head diameter (86.0%). The highest multivariate classification rates are with the scapula (93.5%), os coxa (92.0%), clavicle (89.9%), humerus (89.1%), and ulna (89.1%). This study provides sectioning points to easily estimate sex using Colombian population-specific formulae. This research aids in forensic individuation, as the long bones of the postcranial elements are relatively resistant to taphonomic processes. Furthermore, the ability to achieve such a high degree of success from a single bone is preferable for the fast-paced forensic anthropology laboratories in Colombia that process hundreds to thousands of cases each year. This research plays an important role in the development of population standards in Colombia and South America and provides a robust method that can withstand courtroom scrutiny.

Assuntos