Maximum length of deciduous dentition as an indicator of age during the first year of life: Methodological validation in a contemporary osteological collection.

Out of all the available methods for estimating age at death from immature human skeletal remains, those based on odontometric variables of deciduous dentition have proved to be one of the most accurate. The development of odontometric methods has been improved through the creation of documented human osteological collections, allowing their validation in different populations. The present study aims to test the regression equations for age estimation proposed by Liversidge et al. 1993, Irurita Olivares et al. 2014, and Cardoso et al. 2019, on the basis of the maximum length of deciduous teeth in an Argentinian sample of 35 infants of known age at death. The results showed that the absolute mean difference between estimated and chronological age was 5.76±6.33 weeks for Liversidge's method, 5.71±6.41 weeks for Irurita Olivares's method, and 6.79±5.80 for Cardoso's method. It was also found that, for Liversidge's method, the canines provided the most accurate and the least biased estimations. For Irurita Olivares's method, mandibular anterior teeth were the most accurate, while the first mandibular molars offered the least biased estimations. For Cardoso's method, the canines presented the most accurate estimations, while the lateral incisors the least biased ones. Finally, 95% confidence intervals of estimated ages were calculated for each method, finding that Irurita Olivares's method provided the most reliable age estimations when using mandibular central incisors and mandibular first molars.

Validation of the Third Molar Maturation Index to estimate the age of criminal responsibility in Northeastern Brazil.

The estimation of the age of majority is crucial to determine the legal accountability of an individual. With this purpose, the analysis of the dental development process has proven to be an effective, elucidatory method. This study investigated the applicability of the Third Molar Maturation Index (I3M), proposed by Cameriere et al. (2008), to estimate the age of majority in a sample of Northeastern Brazilians using panoramic radiographs. Adobe® Photoshop® CS4 (Adobe Systems Incorporated, San Jose, California, USA) software was used to obtain the I3M index measurements in a sample of radiographs from a dental radiology clinic located in Northeastern Brazil. Radiographs of individuals aged between 14 and 23 years were included in the sample, except if showing absence, distortions, pathological alterations or suspected pulp impairment of the tooth #38 (third lower left molar), as the method applies exclusively to this element. Of the total sample of radiographs previously obtained for diagnostic and/or orthodontic purposes (n=394), 185 were from males and 209 from females, of which 217 corresponded to 18 year-olds or older and 177 were from minors. Logistic regression and predictive values of sensitivity, specificity and Receiver Operating Characteristic (ROC) curve (α=0.05) were used. The cutoff point originally proposed for the I3M index (0.08) presented a sensitivity of 88.4% and a specificity of 73.2%, with accuracy (area under the ROC curve) of 80.8% (95%CI: 76.4-85.3%) for the Northeastern Brazilian population, as well as a correct age classification in 80.2% of the sample. The method estimated accurately 73.7% of the cases corresponding to "18 years or older" and 88.1% of the cases "under 18years" (p=0.000). Among the sexes, the correct age classification rate of the method was 84.3% for males and 76.6% for females, with no statistically significant difference between the match and error rates and between the sexes (p≥0.05). In conclusion, the Third Molar Maturation Index could accurately distinguish the age of adolescents and young adults of both sexes aged 18 years or under/older in a Brazilian population.

Accuracy of four dental age estimation methodologies in Brazilian and Croatian children.

OBJECTIVE: To compare and analyse the accuracy of four age estimation methods using the mineralisation stages of the permanent teeth (Cameriere et al. [16] [CAM], Liliequist and Lundberg [LLH] and Nolla without third molars [NOL7] or with them [NOL8]) in a mixed population of Brazilians and a homogeneous population of Croatians. METHODS: Orthopantomograms of 930 Brazilians (366 males and 564 females) and 924 Croatians (365 males and 556 females) aged between 8 and 14.99 years were analysed using the CAM, LLH, NOL7 and NOL8 age estimation methodologies. RESULTS: LLH presented the best absolute differences (ADs) among both populations without sex stratification, while CAM presented the worst results. In addition, the mean differences revealed underestimations, except when the LLH and NOL7 methods were used for the Brazilians. When the sample was stratified by sex, the best AD values were found with NOL7 (0.80) for the Brazilians and with LLH (0.98) for the Croatians. When the sample was stratified by sex and age, CAM presented high accuracy at the early ages, and LLH presented high accuracy at the older ages. The results obtained with the Nolla methods (NOL7 and NOL8) were mostly similar, but NOL7 yielded slightly better results. CONCLUSIONS: The values for the Brazilians and the Croatians were relatively similar, and the techniques were properly applied in both population samples. The best method for evaluating both countries was LLH, followed by NOL7, NOL8 and CAM.

Applicability of a pre-established set of facial proportions from frontal photographs in forensic age estimation of a Brazilian population.

Child pornography on the internet is one of the crimes with highest increasing incidence worldwide. In this specific type of crime, the victim's age has important legal implications. To overcome the lack of scientifically established protocols, European researchers explored and proposed a set of facial proportions obtained from images to estimate age. Within a validation scope, the present study aimed to test the applicability of morphological proportions from frontal photographs of the face to estimate age in a Brazilian population. Standardized frontal view photographs from 800 Brazilians (400 females and 400 males) homogeneously distributed in 4 age groups (6, 10, 14 and 18 years ± 30 days) were randomly selected from a Civilian Database of the Brazilian Federal Police. The selected images were analyzed with the aid of cephalometric landmarks. After landmarking the photographs, eighteen metric relations pre-established by Cattaneo et al. (C. Cattaneo, Z. Obertová, M. Ratnayake, L. Marasciuolo, J. Tutkuviene, P. Poppa, D. Gibelli, P. Gabriel, S. Ritz-Timme, Can facial proportions taken from images be of use for ageing in cases of suspected child pornography? A pilot study, Int. J. Leg. Med. 126 2012 139-144) were assessed and analyzed through parametric statistical tests and discriminant analysis. Two indexes had a moderate correlation with age, while ten had a weak correlation and six were not correlated with age. Eleven indexes were statistically different between sexes (p < 0.05). The discriminant analysis showed that 49.6% of the pooled sample was correctly classified into the respective age group. This percentage increased when each sex was analyzed separately: 50.2% for females and 53.5% for males. The set of facial proportions from frontal images proposed by Cattaneo et al. (2012) is related to facial development. As expected, the discriminant power of this approach did not reach optimal effectiveness in the Brazilian sample. In practice, this age estimation method must be adapted for more reliable application in Brazilians.

Forensic anthropology and missing persons: A Brazilian perspective.

The problem of the missing persons phenomenon in Brazil in the 21st century has become apparent, and the responses to the issue are still under development. The relatively new field of forensic anthropology and its trained professionals occupy an essential place in the investigation of cases of missing and unidentified individuals. The development of forensic anthropology in Brazil is unique among Latin American countries, who improved their expertise during the investigations of political crimes that occurred between the 1960s and 1980s in most places. The qualifications and the paths to become a forensic anthropologist in Brazil are different from other professionals who work in the field worldwide. This article addresses the issue of missing person investigations and details the work of forensic anthropologists in such cases in Brazil.

Sex estimation from skull base radiographs in a contemporary Colombian population.

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.

Application and validation of Diagnose Sexuelle Probabiliste V2 tool in a miscegenated population.

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.

The Brazilian identified human osteological collections.

This short communication aims to inform the scientific community of the existence of seven identified osteological collections in Brazil, most of which are housed in universities: 21st Century Collection of the Center for Studies in Forensic Anthropology, Recife; Identified Skeletal Collection of Sergipanos of the University Tiradentes, Aracaju; Identified Skull Collection of the State of Bahia, Aracaju; Osteological and Tomographic Collection - Prof. Dr. Eduardo Daruge, Piracicaba; Osteological Collection of the Institute of Teaching and Research in Forensic Sciences, Guarulhos; Identified Skull Collection of the Anatomy Museum Alfonso Bovero, São Paulo; and the Identified Skull Collection, São Paulo. Three of these collections are from a northeast population, whereas the others are from individuals from the southeast region. Altogether, there are 925 skeletons and more than 998 skulls (three of the referenced collections have only skulls). Data on the number of individuals, sex, age, origin, and dates of inhumation and exhumation are available. This large quantity of identified skeletal remains is a fundamental source of research material that can be used to characterize the Brazilian population and facilitate the development of forensic anthropology. When contextualized within the reference series from South and Central America, it is clear that the Brazilian skeletal reference series hold a position of prominence.

Is "Latin American" population-specific? Testing sex discriminant functions from the Mexican tibia on a Chilean sample.

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.

Validity and accuracy of three radiographic dental age estimation methods in Brazilians.

OBJECTIVE: To validate, analyse accuracy, and construct multiple regression formulae of three age estimation methods - Liliequist and Lundberg, Haavikko, and Mornstad - using mineralization stages of permanent teeth in Brazilians. METHODS: Panoramic radiographs of 1009 Brazilian children and adolescents (387 males and 622 females) aged 8-15.99 years were analysed using the aforementioned methodologies. RESULTS: The overall accuracy (absolute difference=AD and dental age-chronological age=DA-CA) of the methods was as follows: Liliequist and Lundberg, AD=0.97 and DA-CA=-0.58; Haavikko, AD=1.42 and DA-CA=-1.35; and Mornstad, AD=2.48 and DA-CA=0.78. After sex-based stratification, the values for males were as follows: Liliequist and Lundberg, AD=0.91 and DA-CA=-0.45; Haavikko, AD=1.80 and DA-CA=-1.75; and Mornstad, AD=2.74 and DA-CA=1.17. In females, the values were as follows: Liliequist and Lundberg, DA=1.01 and DA-CA=-0.67; Haavikko, AD=1.17 and DA-CA=-1.09; and Mornstad, AD=2.31 and DA-CA=0.53. The Liliequist and Lundberg technique predominated, followed by Haavikko and Mornstad when distinction was present between sex and age. Multiple regression formulae were constructed from the data presented for the Liliequist and Lundberg, Haavikko and Mornstad methodologies. CONCLUSIONS: The validation of the methodologies in the Brazilian population is possible. The Liliequist and Lundberg method most closely represented the Brazilian sample.

A test of four innominate bone age assessment methods in a modern skeletal collection from Medellin, Colombia.

Studying bone collections with known data has proven to be useful in assessing reliability and accuracy of biological profile reconstruction methods used in Forensic Anthropology. Thus, it is necessary to calibrate these methods to clarify issues such as population variability and accuracy of estimations for the elderly. This work considers observations of morphological features examined by four innominate bone age assessment methods: (1) Suchey-Brooks Pubic Symphysis, (2) Lovejoy Iliac Auricular Surface, (3) Buckberry and Chamberlain Iliac Auricular Surface, and (4) Rouge-Maillart Iliac Auricular Surface and Acetabulum. This study conducted a blind test of a sample of 277 individuals from two contemporary skeletal collections from Universal and San Pedro cemeteries in Medellin, for which known pre-mortem data support the statistical analysis of results obtained using the four age assessment methods. Results from every method show tendency to increase bias and inaccuracy in relation to age, but Buckberry-Chamberlain and Rougé-Maillart's methods are the most precise for this particular Colombian population, where Buckberry-Chamberlain's is the best for analysis of older individuals.

Reliability of age estimation from iliac auricular surface in a subactual Chilean sample.

The aim of this study was to test the reliability of Osborne et al. (2004) [8] age estimation based on the iliac auricular surface of the ilium. We selected 172 skeletons with documented sex and age-at-death and established six uniformly distributed age intervals for analysis. ANOVA was employed to assess the association of the documented age with sex and the auricular surface classification. We employed Bonferroni post-hoc tests to find any statistical differences across documented ages within each phase of Osborne's criteria. While the ANOVA showed a significant association between the documented age and the auricular surface classification, post-hoc tests found that phases 2 and 3 were the only consecutive phases with significant differences. We argue that a lack of statistical significance between consecutive phases undermines the reliability of this method for forensic purposes especially in middle adults. It may be possible that the collapse of intermediate phases would increase the accuracy of this method.

Sex estimation from the scapula in a contemporary Chilean population.

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%.

Macromorphoscopic trait expression in a cranial sample from Medellín, Colombia.

Adjusting existing methods of human identification developed by forensic anthropologists in the United States for use with populations not included in the original development of an analytical method requires data collection using contemporary osteological collections from those populations, and an assessment of the within-group variation present. The primary purpose of this research is to document cranial macromorphoscopic trait variation using methods previously developed in the United States in a sample of 244 individuals from Antioquia, Medellín, Colombia. All individuals are of known age, sex, and birth region. The complex population and demographic history of Colombia makes ancestry assessment particularly difficult in that country. To that end, we explore inter-regional variation throughout Antioquia using birthplace to determine whether forensic anthropologists can provide finer levels of detail beyond identifying an unknown set of human remains as 'Colombian' or, more generally, Hispanic. State and local levels of identification resulting from the varied population histories of each state within Antioquia permit finer resolution, but only to a degree of certainty. Artificial neural networks (aNN) correctly classified only 18.6% of a validation sample, following modest classification accuracies of test/tuning (11.6%) and training (82.8%) samples to original birthplace. As with most neural networks, overfitting is an issue with these analyses. To remedy this overfitting and to document the applicability of aNNs to the assessment of ancestry in Colombia, we pooled the sample of Colombian data and compared that to modern American samples. In those analyses, the best aNN model correctly classified 48.4% (validation) of the sample. Given these results, finer levels of analysis in Colombia are not yet possible using only macromorphoscopic trait data.

A contemporary Colombian skeletal reference collection: A resource for the development of population specific standards.

Several authors who have discussed human variability and its impact on the forensic identification of bodies pose the need for regional studies documenting the global variation of the attributes analyzed osteological characteristics that aid in establishing biological profile (sex, ancestry, biological age and height). This is primarily accomplished by studying documented human skeletal collections in order to investigate secular trends in skeletal development and aging, among others in the Colombian population. The purpose of this paper is to disclose the details of the new "Contemporary Colombian Skeletal Reference Collection" that currently comprises 600 identified skeletons of both sexes, who died between 2005 and 2008; and which contain information about their cause of death. This collection has infinite potential for research, open to the national and international community, and still has pending opportunities to address a variety of topics such as studies on osteopathology, bone trauma and taphonomic studies.

Comparison of accuracy between dental and skeletal age in the estimation of chronological age of Down syndrome individuals.

This study aimed to evaluate the accuracy of dental age (DA) and skeletal age (SA) methods in order to estimate chronological age (CA) in individuals with Down syndrome (DS), contributing to the Forensic Dentistry and making the identification of these individuals age possible. For this, 278 images of individuals were selected and divided in 2 groups: 216 non-DS patients and 62 with DS. At first, DA was evaluated by Nolla method, on panoramic radiographs, followed by SA, evaluated by Greulich and Pyle method. The linear correlation coefficient of Pearson was used for the analysis of concordance between the methods. Paired t-test with confidence interval was used to evaluate the accuracy and Bland and Altman method was applied to estimate limits of concordance. Complementary to this first analysis, descriptive statistics and ANOVA test were applied for comparison among chronological age (CA), dental age (DA) and skeletal age (SA), with a significance level of 95% (p≥0.05), ordering to observe the differences among them. DA, estimated by Nolla, is underestimated in both, DS and non-DS individuals, and it is more notable in DS individuals. SA estimated by Greulich and Pyle method is overestimated, except for non-DS males. The range of variance is greater in SA and DS than DA and non-DS individuals, respectively. A greater accordance was found for DA×CA if compared to SA×CA, indicating that DA, estimated by Nolla method, is more accurate than SA, evaluated by Greulich and Pyle method, for estimating CA of both, DS and non-DS individuals. However, neither method seems to be precise and more caution is required for age estimation in DS individuals.

Equations to estimate fetal age at the moment of death in the Mexican population.

Metric standards are presented for the estimation of fetal age at the time of death in the Mexican population. To obtain these standards, both metric and radiological studies were conducted on 97 fetuses and complete stillborn infants of both sexes, phenotypically normal between 10 and 38 weeks of morphological age. All the fetuses used were the product of spontaneous abortions in Mexico City between 1990 and 2000. Equations were obtained by calibrating quadratic linear regression models adjusted for the diaphyseal length of the humerus, radius, ulna, femur, tibia and fibula, characterized as the most adequate indicators to represent the growth of long bones in this age group, and verified by the evaluation of the model assumptions and the coefficient of determination (R(2)). To conclude, these models facilitate a more precise prediction in fetuses of the Mexican population, constituting the first metric standards of their type at a national level.

Metric sex estimation from the postcranial skeleton for the Colombian population.

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.

Sex determination using the mesio-distal dimension of permanent maxillary incisors and canines in a modern Chilean population.

The pelvis and skull have been shown to be the most accurate skeletal elements for the determination of sex. Incomplete or fragmentary bones are frequently found at forensic sites however teeth are often recovered in forensic cases due to their postmortem longevity. The goal of the present research was to investigate sexual dimorphism between the mesio-distal dimension of the permanent maxillary incisors and canines for the determination of sex in a contemporary Chilean population. Three hundred and three dental models (126 males and 177 females) from individuals ranging in age from 13 years to 37 years old were used from the School of Dentistry, University of Chile. The statistical analyses showed that only the central incisors and canines were sexually dimorphic. Discriminant function score equations were generated for use in sex determination. The average accuracy of sex classification ranged from 59.7% to 65.0% for the univariate analysis and 60.1% to 66.7% for the multivariate analysis. Comparisons to other populations were made. Overall, the accuracies ranged from 54.4% to 63.3% with males most often identified correctly and females most often misidentified. The determination of sex from the mesio-distal width of incisors and canines in Chilean populations does not adhere to the Mohan and Daubert criteria and therefore would not be presented as evidence in court.

Quantitative assessment of the facial features of a Mexican population dataset.

The present study describes the morphological variation of a large database of facial photographs. The database comprises frontal (386 female, 764 males) and lateral (312 females, 666 males) images of Mexican individuals aged 14-69 years that were obtained under controlled conditions. We used geometric morphometric methods and multivariate statistics to describe the phenotypic variation within the dataset as well as the variation regarding sex and age groups. In addition, we explored the correlation between facial traits in both views. We found a spectrum of variation that encompasses broad and narrow faces. In frontal view, the latter is associated to a longer nose, a thinner upper lip, a shorter lower face and to a longer upper face, than individuals with broader faces. In lateral view, antero-posteriorly shortened faces are associated to a longer profile and to a shortened helix, than individuals with longer faces. Sexual dimorphism is found in all age groups except for individuals above 39 years old in lateral view. Likewise, age-related changes are significant for both sexes, except for females above 29 years old in both views. Finally, we observed that the pattern of covariation between views differs in males and females mainly in the thickness of the upper lip and the angle of the facial profile and the auricle. The results of this study could contribute to the forensic practices as a complement for the construction of biological profiles, for example, to improve facial reconstruction procedures.