Comparison of Four Skeletal Methods for the Estimation of Age at Death on White and Black Adults

Age determination by measurement of pulp volume of canine teeth in patients with cleft lip and palate: a retrospective study

OBJECTIVES

This study evaluates the potential of pulp volume/total tooth-volume measurements of canine teeth in relation to chronologic age in patients with cleft lip and palate (CLP). The significance of this study lies in its exploration of the usability of these measurements for age determination in CLP patients, providing a novel perspective to the existing literature.

METHODS

Cone beam computed tomography images of 33 patients (16 females, 17 males) with unilateral CLP aged 14-45 years and 33 age- and sex-matched healthy individuals (16 females, 17 males) were retrospectively evaluated. Using ITK-SNAP software, pulp and whole tooth volumes of canine teeth on the non-defect side of CLP patients and the corresponding side of healthy individuals were measured. Their relationship with chronologic age was evaluated, and comparisons were made between the CLP and control groups.

RESULTS

No statistically significant difference was observed between the whole tooth volume, pulp volume, and pulp volume/total tooth-volume ratios of the control and CLP groups. A paired t test comparing chronologic age and calculated mean age of both groups found no significant difference.

CONCLUSIONS

The results show that the pulp and total tooth-volume ratios of canine teeth in the non-defect areas of individuals with unilateral CLP correlate with chronologic age and can be used reliably for age determination. This indicates that individuals with CLP can be evaluated similarly to healthy individuals, allowing accurate age estimation based on dental measurements.

Evaluating the accuracy of root transparency and periodontosis age estimation models in a Portuguese population

This study aims to evaluate the accuracy of existing dental age estimation models, including the Lamendin, Prince & Ubelaker, Fialho, and modified Fialho methods, within a Portuguese population. Dental techniques, particularly those involving root transparency and periodontosis, are examined due to their relevance in forensic age estimation. A sample of 166 single-rooted teeth from individuals aged 30 to 86 was analyzed. Measurements included root transparency, periodontosis, and tooth and root length. Statistical methods were applied to assess the reliability and accuracy of each model in estimating age, considering the potential influence of environmental and lifestyle factors on dental aging. Root transparency emerged as a robust age indicator, consistently correlating with chronological age. In contrast, periodontosis introduced variability due to external influences, reducing its reliability. The modified Fialho model, which focuses solely on root transparency, showed the highest accuracy, suggesting that eliminating periodontosis from the estimation process may enhance reliability in populations where environmental factors heavily affect dental aging. The findings underscore the importance of population-specific adjustments in dental age estimation models. By refining methods like the modified Fialho model, forensic investigations can achieve more accurate results, particularly in populations where external factors influence periodontosis.

Forensic International Dental Database (FIDBv2) for adult age-at-death estimation in multiple forensic contexts: Strengthening the operationalization of the Lamendin criteria in a global scope model

The aim of this study is to validate the FIDBv2 online procedure for adult age-at-death estimation using root dentine translucency (RDT) and periodontal retraction (PR) of single-rooted teeth in a worldwide sample. The sample includes 4810 teeth of 2559 individuals from 16 countries of America, Europe and Asia. Bias and inaccuracy between documented (DA) and estimated ages (EA) were calculated. Pearson and Intraclass Correlation Coefficients were computed to assess the strength of agreement between pairs of data, while Kolmogorov-Smirnov Z was used to evaluate the statistical significance of the differences. The percentages of correctly estimated cases within different age ranges were obtained to find trends in the reliability of the results. Most of the biases (-4.61-1.31 years) and inaccuracies (4.81-9.72 years) are low. The dispersion of EA increases with age and almost all the DA-EA correlations are above 0.75. DA-RDT and DA-PR correlations are positive, most of the former being high (0.74-0.91), and the latter being low (0.11-0.54). The highest percentages of correct estimations are identified for the ±7.5 and ±10 years ranges, and most comparisons of bias and inaccuracy between countries are non-significant. The high correlations between DA and EA suggest that the method is robust and reliable for a global application. Mean errors are low, with the best results found in the 30-69-year-old cohort. This research supports that the method is effective and accurate for age estimation in forensic contexts worldwide, thus reaffirming it is a generalizable procedure locally and internationally.

Applicability of the six-phase method for auricular age estimation in an Indian population: A CT-based study

Age estimation plays a crucial role in human identification. Amongst numerous age markers located throughout the skeletal framework, the auricular surface of the ilium presents as a resilient structure, with different methods for auricular age estimation currently in practice. Amongst these methods, the Osborne method is believed to permit accurate age estimation through its use of robust age categories and discrete phase descriptors. The present study aimed to assess the applicability of the Osborne method in an Indian population through a computed tomographic (CT) examination of the auricular surface, an aspect presently unreported. In order to do so, CT scans of 380 individuals were collected and evaluated using the Osborne method. A CT-based examination indicated that surface texture described by Osborne is difficult to appreciate through 3D CT images. Indistinct definitions associated with certain features, and the mosaic display of features within each phase further prevents applying the method effectively. Overall accuracy percentages of 99.47% and 98.90% were obtained using the method in males and females, respectively, with corresponding inaccuracy values of 10.10 years and 9.04 years. Significantly reduced accuracy percentages were obtained with alternate, more robust age brackets presented within the original study, demonstrating the limited reliability associated with the method. Inaccuracy and bias values computed for each decade indicate the relative utility of the method in aging 40-59-year-old individuals. Low accuracy percentages, high error rates and different methodological hindrances encountered within the present study illustrate the limited applicability of the Osborne method in aging an Indian population.

Mandibular torus thickness associated with age: Postmortem computed tomographic analysis

Age estimation is an essential step in identifying human corpses. Several mandibular landmarks have been highlighted as skeletal sites for age estimation since aging causes morphological changes. Reports suggest that mandibular torus size may be associated with aging; however, thorough investigation has not been performed owing to the difficulty in measuring it. Therefore, this study aimed to determine the association between age and mandibular torus thickness using postmortem computed tomography data from Japanese corpses. This study included 2,792 corpses with mean (standard deviation) age of 58.0 (22.4) years (range, 0-101 years) and 67.6 % males. Further, 2,662 (95.3 %), 14 (0.5 %), 59 (2.1 %), and 57 (2.0 %) corpses were in the permanent, mixed, primary, and predental dentition periods, respectively. Multivariable analysis was performed to quantify the impact of age on mandibular torus thickness, adjusting for sex, height, weight, and occlusal contact status. The model also included an interaction term between age and occlusal status because of the potential effect modification by occlusion. Results of the multivariable regression analysis showed that mandibular torus thickness increased with age (the regression coefficients (95 % confidence interval) were 0.6 (0.2-1.0), 0.7 (0.3-1.0), 1.0 (0.6-1.4), 1.3 (0.9-1.7), 1.3 (0.8-1.8), and 1.1 (0.4-1.7) for age groups 30-39, 40-49, 50-59, 60-69, 70-79, and 80-89 years, respectively), especially in males with occlusal contact. A significant association between mandibular torus thickness and age, modified by occlusal status and sex, was identified. Therefore, data regarding the thickness of the mandibular torus and occlusal status may be useful for age estimation in human corpses.

Testing the accuracy of the DRNNAGE software for age estimation in a modern Greek sample

Estimation of age-at-death from human skeletal remains is fundamental in forensic anthropology as part of the construction of the biological profile of the individual under study. At the same time, skeletal age-at-death estimation in adults is problematic due to the disparity between chronological and biological age, the important inter-individual variability at the rate of skeletal aging, and inherent biases in the available methodologies (e.g., age mimicry). A recent paper proposed a method for skeletal age-at-death estimation based on multiple anatomical traits and machine learning. A software was also created, DRNNAGE, for the easy implementation of this method. The authors of that study supported that their methods have very high repeatability and reproducibility, and the mean absolute error of the age estimation was ~6 years across the entire adult age span, which is particularly high and promising. This paper tests the proposed methodology on a modern documented Greek sample of 219 adult individuals from the Athens Collection, with age-at-death from 19 to 99 years old. The sample was split into males and females as well as into individuals under and over 50 years old. We also divided the sample in 10-year intervals. First, intra- and inter-observer error was estimated in order to assess repeatability and reproducibility of the variables employed for age-at-death estimation. Then, the validity (correct classification performance) of DRNNAGE for each anatomical region individually, as well as all combined, was evaluated on each demographic separately and on the pooled sample. According to the results, some of the variables showed very low repeatability and reproducibility, thus their use should be cautious. The DRNNAGE software showed overall highly accurate age-at-death estimates for individuals older than 50 years, but poor on younger adults, with only exception the cranial sutures, which performed surprisingly well for all age groups. Overall, these results support the importance of cross-validation and the use of population-specific methods in forensic anthropology.

Applicability of the Suchey-Brooks method for age estimation in an Indian population: A computed tomography-based exploration using Bayesian analysis and machine learning

Age estimation occupies a prominent niche in the identification process. In cases where skeletal remains present for examination, age is often estimated from markers distributed throughout the skeletal framework. Within the pelvis, the pubic symphysis constitutes one of the more commonly utilized skeletal markers for age estimation, with the Suchey-Brooks method comprising one of the more commonly employed methods for pubic symphyseal age estimation. The present study was targeted towards assessing the applicability of the Suchey-Brooks method for pubic symphyseal age estimation, an aspect largely unreported for an Indian population. In order to do so, clinically undertaken pelvic computed tomography scans of individuals were evaluated using the Suchey-Brooks method, and the error associated with the method was established using Bayesian analysis and different machine learning regression models. Amongst different supervised machine learning models, support vector regression and random forest furnished lowest error computations in both sexes. Using both Bayesian analysis and machine learning, lower error computations were observed in females, suggesting that the method demonstrates greater applicability for this sex. Inaccuracy and root mean square error obtained with Bayesian analysis and machine learning illustrates that both statistical modalities furnish comparable error computations for pubic symphyseal age estimation using the Suchey-Brooks method. However, given the numerous advantages associated with machine learning, it is recommended to use the same within medicolegal settings. Error computations obtained with the Suchey-Brooks method, regardless of the statistical modality utilized, indicate that the method should be used in amalgamation with additional markers to garner accurate estimates of age.

Three decades after the publication of the Lamendin method for adult age-at-death estimation: Methodological evolution of the procedure and interpretations

More than three decades have passed since the publication of Lamendin et al.'s proposal in 1992. Over this time, numerous investigations have been conducted to assess the applicability of the technique in different populations with acceptable results in terms of estimation errors. The proposal by Lamendin and colleagues remains relevant today, and has made a significant contribution to adult age-at-death estimation due to its simplicity, repeatability, replicability, and high performance. Indeed, significant progress towards systematizing and strengthening the procedure has been reported in the published literature. One noteworthy advancement is the development of an international database that supports the use of Bayesian statistics for age-at-death estimation. This resource plays a crucial role in standardizing the methodology and improving the reliability for obtaining more reliable results on a global scale. The aim of this study is to investigate the historical evolution of the technique, to assess the accuracy of the results obtained by different analytic procedures, and to explore its impact in forensic applications through a systematic analysis of the specialized literature on this field. The current state of research indicates that this type of methodological research is an ongoing process, far from being completed. Many questions and challenges that require further attention to address effectively these issues remain unanswered, such as the development of non-linear regressions and probabilistic approaches, the deepening of procedures that improve global approximations, and the intensification of research focused on achieving more accurate estimations among individuals over 70 years-old. However, studies generally agree that the Lamendin technique works well for individuals between the ages of 30-60 years. It is still in force today, although the method has been significantly perfected. Despite the degree of research development in this area, further efforts are needed to improve the understanding and performance of these kinds of procedures. This will ultimately lead to an improvement in the accuracy and reliability of forensic investigation results worldwide.

Age estimation in the combined long bones and ribs by histomorphometry: Past, present, and future

Numerous age estimation methods in unidentified bone have been a long time developing for application in forensic anthropology. The histomorphometric technique is one of the alternative methods that relied upon the evaluation of the cortical bone microstructure over the lifespan as a result of the remodeling process in bone. Remodeling is a sophisticated event occurring from the coupled function of bone formation and resorption cells for maintaining mineral homeostasis and repairment of microdamage in bone tissue. Products derived from remodeling are primary changes in the osteon or haversian system in various regions in the cortical bone, including periosteum, endosteum, and trabecular bone. Throughout life, bone remodeling rate with osteon alteration can be predictable. In the forensic field, histological methods are getting more attention due to the unavailability of macroscopic methods. Histomorphometry approach can be accomplished in fragmentary or incomplete bone remains indicating the limited use of gross morphological methods. In addition, the microscopic methods can aid to increase the more accuracy of analyses and diminish the biased subjective assessment for determining age. Most histomorphometry method utilizes a cross-section of the midshaft of the long bones including the mandible, rib, and clavicle. This review provides the basic knowledge of bone biology and anatomy, several age-estimating methods of histology, and crucial factors for age methods. Studies regarding overall age determination methods from the past until now contribute to obtaining more benefits for developing methods of histomorphometry using human bone in forensic identification.

The panoramic radiograph archive of the human craniological collection housed at the Human Anatomy Museum in Turin

The craniological collection at the Human Anatomy Museum of the University of Turin consists of 1090 skulls and 64 postcranial skeletons prepared mostly during the second half of the nineteenth century. The collection presents individuals of both sexes and of different age groups and includes 712 skulls of known age and sex and 378 of which only the sex is known. Most individuals are associated with a documentation that includes sex, age-at-death, dates of birth and a death certificate. The collection comes from several regions of Italy, between 1880 and 1915, received by the former Anatomical Institute of the University of Turin from city's prisons and hospitals. The whole craniological collection of known age was subjected to panoramic radiographs. The craniological collection combined with the panoramic digital X-ray images represents an important contribution in anthropology and forensic odontology, as there is now no craniological collection available in the world available from a radiological perspective, for investigating dental age assessment and sex dimorphism using radiographs as well as other research and teaching potentials.

Forensic age estimation: comparison and validation of the Iscan method in 3D reconstructions using a surface scanner in a Spanish population

When investigating a death, post-mortem identification provides with results of great legal and humanitarian significance. The effectiveness of the methods used to estimate age depends on the reference population, considering variables such as sex and ancestry. The aim of this study was to validate the Iscan method to estimate age in a Spanish forensic population, comparing the estimates obtained in dry bones and 3D reconstructions created with a surface scanner. We carried out a cross-sectional study on 109 autopsied corpses (67% male), scanning the sternal end of the right fourth rib in a 3D mesh, using an EinScan-Pro® surface scanner (precision: 0.05 mm). Two observers estimated the phases in dry bones and 3D images according to the Iscan method and to the sex of the subject. The mean age was 57.73 years (SD = 19.12 years;18-93 years). The intra-observer agreement was almost perfect in bones (κ = 0.877-0.960) and 3D images (κ = 0.954), while the inter-observer agreement was almost perfect in bones (κ = 0.813) and substantial in 3D images (κ = 0.727). The correlation with the Iscan phases was very strong in bones (Rho = 0.794-0.820; p < 0.001) and strong in 3D images (Rho = 0.690-0.691; p < 0.001). Both sex-adjusted linear regression models were significant (dry bones: R2 = 0.65; SEE =  ± 11.264 years; 3D images: R2 = 0.50; SEE =  ± 13.537 years) from phase 4 onwards. An overestimation of age was observed in the first phases, and an underestimation in the later ones. Virtual analysis using a surface scanner in the fourth rib is a valid means of estimating age. However, the error values and confidence intervals were considerable, so the joint use of different methods and anatomical sites is recommended.

Root dentin translucency and age at death estimation in adults using single rooted teeth: Update of the Forensic International Dental Database

Since the publication of Lamendin's age estimation technique, the root dentin translucency has received increasing attention as an important indicator of age. Recently, Parra and colleagues presented the Forensic International Dental Database (FIDB), a proposal to estimate age at death in adults based on Bayes theorem by applying the criteria of Lamendin's technique. The present study aims to update the procedure and to evaluate a new version of the method (named FIDBv2) using two control samples from Colombia and Greece. The performance of this new version was acceptable and suggests that the method is suitable for age at death estimation in adult individuals from different forensic contexts. The best approximations to chronological age were obtained for individuals between 30 and 60 years old, with errors less than 10 years. The age estimations calculated on control samples suggest the adequate performance of FIDBv2 on individuals from varied populations. It can be stated that the FIDBv2 constitutes a solid alternative to be used in contexts where no additional data are available. Here we reinforce the initial idea that this model for estimating age at death in adults may be generalizable to any forensic context in the world.

Paleodemography: From archaeology and skeletal age estimation to life in the past

Much of paleodemography, an interdisciplinary field with strong ties to archaeology, among other disciplines, is oriented toward clarifying the life experiences of past people and why they changed over time. We focus on how human skeletons contribute to our understanding of preindustrial demographic regimes, including when changes took place that led to the world as we know it today. Problems with existing paleodemographic practices are highlighted, as are promising directions for future work. The latter requires both better age estimates and innovative methods to handle data appropriately. Age-at-death estimates for adult skeletons are a particular problem, especially for adults over 50 years that undoubtedly are mistakenly underrepresented in published studies of archaeological skeletons. Better age estimates for the entirety of the lifespan are essential to generate realistic distributions of age at death. There are currently encouraging signs that after about a half-century of intensive, and sometimes contentious, research, paleodemography is poised to contribute much to understandings of evolutionary processes, the structure of past populations, and human-disease interaction, among other topics.

The computational age-at-death estimation from 3D surface models of the adult pubic symphysis using data mining methods

Age-at-death estimation of adult skeletal remains is a key part of biological profile estimation, yet it remains problematic for several reasons. One of them may be the subjective nature of the evaluation of age-related changes, or the fact that the human eye is unable to detect all the relevant surface changes. We have several aims: (1) to validate already existing computer models for age estimation; (2) to propose our own expert system based on computational approaches to eliminate the factor of subjectivity and to use the full potential of surface changes on an articulation area; and (3) to determine what age range the pubic symphysis is useful for age estimation. A sample of 483 3D representations of the pubic symphyseal surfaces from the ossa coxae of adult individuals coming from four European (two from Portugal, one from Switzerland and Greece) and one Asian (Thailand) identified skeletal collections was used. A validation of published algorithms showed very high error in our dataset-the Mean Absolute Error (MAE) ranged from 16.2 and 25.1 years. Two completely new approaches were proposed in this paper: SASS (Simple Automated Symphyseal Surface-based) and AANNESS (Advanced Automated Neural Network-grounded Extended Symphyseal Surface-based), whose MAE values are 11.7 and 10.6 years, respectively. Lastly, it was demonstrated that our models could estimate the age-at-death using the pubic symphysis over the entire adult age range. The proposed models offer objective age estimates with low estimation error (compared to traditional visual methods) and are able to estimate age using the pubic symphysis across the entire adult age range.

Adult Skeletal Age-at-Death Estimation through Deep Random Neural Networks: A New Method and Its Computational Analysis

Age-at-death assessment is a crucial step in the identification process of skeletal human remains. Nonetheless, in adult individuals this task is particularly difficult to achieve with reasonable accuracy due to high variability in the senescence processes. To improve the accuracy of age-at-estimation, in this work we propose a new method based on a multifactorial macroscopic analysis and deep random neural network models. A sample of 500 identified skeletons was used to establish a reference dataset (age-at-death: 19–101 years old, 250 males and 250 females). A total of 64 skeletal traits are covered in the proposed macroscopic technique. Age-at-death estimation is tackled from a function approximation perspective and a regression approach is used to infer both point and prediction interval estimates. Based on cross-validation and computational experiments, our results demonstrate that age estimation from skeletal remains can be accurately (~6 years mean absolute error) inferred across the entire adult age span and informative estimates and prediction intervals can be obtained for the elderly population. A novel software tool, DRNNAGE, was made available to the community.

Contribution of the use of clavicle bone density in age estimation

Age estimation is an essential element in the field of forensics and is also of judicial interest in forensic medicine of the living. Despite all the methods, age estimation is often imprecise with many biases, especially in mature individuals. The main objective of our study is to assess the correlation between age and computed tomography bone mineral density of the medial end of the clavicle. A sample of 180 chest multi-slice computed tomography scans without contrast injection performed in living individuals, with suspected respiratory infection, aged 15 to 100 years was used. Bone density measurement was performed on the medial meta-epiphyseal region of the clavicles. A significant negative correlation was found between bone density and age of individuals (p-value < 0.05). The mean absolute error was calculated for men at 13.4 years and 13.1 years for women, which was associated with an absence of bias. Good precision of the estimate for both sexes was also calculated on a subgroup of individuals whose age was greater than 40 years, with average absolute errors of about 12 years, which was associated with an absence of relative error. In view of our preliminary results, the study of bone density of the medial end of the clavicle could be of interest in the estimation of age. Several studies will be necessary to evaluate the reproducibility of these results on independent bone samples and in the estimation of age in the living individual.

Assessment of renal glomerulosclerosis and thickness of the carotid intima-media complex as a means of age estimation in Western European bodies

INTRODUCTION

The estimation of age-at-death of unidentified cadavers is a central aspect of the identification process. With increasing age, the incidence of glomerulosclerosis and the thickness of the carotid wall have been observed to also increase. This correlation has been demonstrated in various international histological studies. The aim of our study was to assess whether these correlations also apply to a Western European population.

METHODOLOGY

In this retrospective observational study, kidney and common carotid artery samples from 216 cases autopsied at the Institute of Legal Medicine at the Justus-Liebig University in Giessen, Germany, were examined. Only cases with available tissue samples from both body sides were included. Exclusion criteria were poor sample quality and an age younger than 21 years. After histological processing, the tissue samples were assessed and digitally evaluated. Regression and classification analyses were used to investigate the correlation between age-at-death and intima-media thickness and age-at-death and the incidence of renal glomerular sclerosis.

RESULTS

Of the 216 autopsy cases, 183 were included for evaluation. Analysis of the carotid artery segments showed a strong correlation (Pearson correlation coefficient r = 0.887) between the intima-media-complex thickness and chronological age. Classification of the glomerulosclerotic incidence showed a correlation of 37.7-43.1% with the predicted age group.

DISCUSSION

Both the intima-media thickness and the proportion of sclerotic glomeruli can be used to estimate age in Western European cadavers. On the basis of these results, both methods are suited to supplement other already established methods for age-at-death estimation in the identification of an unknown cadaver.

Age-at-death estimation in adults using three forensic methodologies: A Lamendin's technique approach for Latin American context and the extension of a forensic international dental database

In forensic science, the information that teeth provide to the age estimation process is very important. In adults, one of the most widely used indicators of skeletal age is the Root Dentin Translucency (RDT), mainly through the Lamendin technique, which is used in various Latin American contexts. Recently, Parra et al. (2020) have developed a Bayesian regression model using the Lamendin technique to establish standardized criteria for estimating age-at-death in adults in various forensic contexts. In this study, we evaluate the applicability of this proposal together with the proposal by Lamendin et al. (1992) and Prince and Ubelaker (2002) in Latin American contexts. A sample of single-rooted teeth belonging to 805 individuals from six Latin American countries was used. The results of the three proposals considered were analyzed taking into account factors such as age, sex, origin, and the tooth surface on which the variables were surveyed. Of the factors that would affect the estimates, it was found that the age of the individuals had the greatest influence. However, it was confirmed that the sex and surface of the teeth on which the measurements were taken did not influence the final result. On the other hand, as we expected, the application of the analyzed proposals would also be possible in other forensic contexts, as shown by the results obtained according to the origin. This research expands the FIDB with more information on Latino contexts.

The accuracy and reliability of the Suchey-Brooks pubic symphysis age estimation method: Systematic review and meta-analysis

Suchey-Brooks method has been studied many times with varying reports of accuracy and reliability. A systematic review and meta-analyses were utilized to quantitatively determine the accuracy and reliability of the Suchey-Brooks (S-B) method. A systematic search of PubMed and EBSCO health and medical databases was performed. Meta-analyses were performed to quantify the relationship between actual known age at death and the S-B method using Spearman's Rho and Pearson's r for (1) combined males and females estimates, (2) male-only estimates, and (3) female-only estimates. Overall correlation coefficient using Cohen's kappa, Spearman's Rho, and Pearson's r was also calculated to determine the interrater and intrarater reliability using the S-B method. Eighteen studies classified as moderate-to-high methodological quality met the inclusion criteria. The sample sizes were different for the combined male and female (n = 2620), male-only (n = 2602), and female-only (n = 1431) meta-analyses. The effect size of the age at death meta-analyses was large and significant for combined males and females (Spearman's Rho = 0.62; Pearson's r = 0.65), male-only (Spearman's Rho = 0.77; Pearson's r = 0.75), and female-only (Spearman's Rho = 0.71; Pearson's r = 0.71). The overall correlation coefficients of the interrater (Kappa = 0.76; Spearman's Rho = 0.73; Pearson's r = 0.80) and intrarater (Kappa = 0.81; Spearman's Rho = 0.91; Pearson's r = 0.83) reliability meta-analyses were large and significant. A significant degree of heterogeneity was present in all meta-analyses, with minimal evidence of publication bias. The meta-analyses results suggest the S-B method is highly reliable with a moderate-to-high degree of accuracy. Our results also identified sample size and accuracy differences between male and female individuals.

Forensic anthropology casework performance: Assessing accuracy and trends for biological profile estimates on a comprehensive sample of identified decedent cases

The purpose of this study was to investigate the accuracy rates and trends in forensic anthropology casework concerning the estimation of the biological profile (sex, age, ancestry, and stature). Identified cases from the Forensic Anthropology Database for Assessing Methods Accuracy (FADAMA; n = 359) were analyzed to explore the following: accuracy rates per biological profile component, case-level performance in assessing the biological profile, and factors related to inaccuracy rates. Accuracy rates for the four biological profile components ranged from 83% to 98%, with sex estimation performing the best and stature performing the poorest. While the overall sex estimation inaccuracies were the lowest of any biological profile component, we found that females are missexed approximately ten times more often than males. Inaccurate age estimates were more frequently the result of overestimation than underestimation, while the trends are reversed for stature estimation. Regarding ancestry estimation performance, African American/Black and White decedents had the lowest inaccuracy rates, while Hispanic and Asian/Pacific Islander decedents demonstrated greater inaccuracy rates. When examining accuracy rates for each case, 81% of cases had no inaccurate biological profile estimates, while 17% and 2% inaccurately estimated one and two biological profile components, respectively. The demographic trends of identified forensic anthropology cases reflect the national unidentified decedent demographics. Biological profile accuracy rates were generally comparable to previous studies. The findings highlight the current status of forensic anthropologists' casework performance, with a greater amount of case-level inaccuracy rates than previously thought, and demonstrate the potential methodological and sampling strategies that could improve accuracy rates.

Computed tomographic age estimation from the pubic symphysis using the Suchey-Brooks method: A Systematic Review and Meta-analysis

Forensic age estimation is routinely applied in investigations involving identification of individuals. Over the past century a myriad of methods have been devised for age estimation. One such method, proposed by Suchey and Brooks in 1990, groups the observed changes occurring in the pubic symphysis into six phases, each defined by a corresponding age range. The present study was piloted with the focussed question being to empirically determine the accuracy of the Suchey-Brooks method in computed tomographic age estimation by analysing morphological changes occurring in the pubic symphysis. Original articles pertaining to the use of the Suchey-Brooks method for CT based age estimation were extracted from four different databases- PubMed, CENTRAL, Google Scholar and ScienceDirect. Research papers which were answering the focussed question were selected for data analysis. After assessing the risk of bias of the selected articles, the data was subjected to Meta-analysis. Pooled analysis of correctly/accurately aged individuals/remains using the random and fixed effect models yielded a prediction percentage of 78% and 86%, respectively. Higher percentages were obtained for phase-wise and subgroup analysis, indicating that the Suchey-Brooks method is a reliable method for age estimation.

Root Dentin Translucency and Forensic International Dental Database: Methodology for estimation age-at-death in adults using single-rooted teeth

Estimation of the age-at-death in adults is essential when the identification of deceased persons with unknown identity is required in both humanitarian and judicial contexts. However, the methodologies and the results obtained can be questioned. Various efforts have been developed to adjust procedures to specific populations, always seeking the precision and accuracy of the methodologies. It is known that the estimation of the age-at-death in adults coexists with wide margins of error, due to several reasons, including but not limited to statistical problems, the size of the sample or the physiological process of aging. This research focuses on a degenerative indicator of the dentin (Root Dentin Translucency) and its combination with Periodontal Height (PH) following the Lamendin's technique for estimation of the age-at-death in adults. The main objective of this research was to demonstrate the applicability of a Bayesian model based on a Forensic International Dental Database (FIDB) that include Root Translucency Height (RTH) and PH as a method to age-at-death in adults. The conclusion of this research was that the combined both indicators become a generalizable age-at-death in adults model for all human populations, where the Bayesian method would offer optimal results in any population. In this way, those populations that do not have had the possibility of validating a specific procedure, now have the opportunity to apply a valid method for estimating age-at-death in adults to global scope.

Application and analysis of the Rissech acetabular adult aging method in a Colombian sample

The classical age indicators of the innominate have been the pubic symphysis and auricular surface. However, recently, the acetabulum has been highlighted as an indicator of adult age, with applicability in young, middle-aged, and older adults. The Rissech acetabular method was developed in a Portuguese population and tested in European and European-Americans, giving estimates within 10 years of age in more than 89% of the sample. The main goal of this paper is to test the Rissech acetabular method in a modern South American sample. The material used for the study was 184 women and 378 men from a Colombian-documented skeletal collection. The obtained morphological scores from the acetabulum were analyzed through the IDADE2 web page, a Bayesian statistical program that estimates a relative likelihood distribution for the target individuals, produces age estimates, and provides 95% confidence intervals. Results showed this method is useful in the modern Colombian population with an average absolute error of 10.63 years in females and 9.44 years in males. These errors are similar to those obtained in other European and North American samples when this method was performed and similar or lower than those obtained when the 3 classical aging methods (Suchey-Brooks, Buckberry-Chamberlain, and Lovejoy) were applied in the same collection (absolute error: 10.29 years ♀ and 9.05 years ♂ in Suchey-Brooks, 12.5 years ♀, and 12.17 years ♀ in Buckberry-Chamberlain, and 13.54 years ♀ and 10.99 years ♂ in Lovejoy). Although Rissech's method was developed in a Western European sample, the results of this study indicate its applicability in modern Colombian samples with reasonable accuracy.

Forensic age estimation based on the pigmentation in the costal cartilage from human mortal remains

Age estimation is considered a crucial and challenging issue in forensic casework. Costal cartilage appears a potential mortal remain in age-at-death estimation attributable to its correlative alteration in color based on pigment accumulation with the advancing age. In this study, samples from the second costal cartilage were collected in a Chinese Han population, and the cross sections were subsequently scanned and digitalized in a standard way. Color change was quantified using mean gray value (MGV), which was measured by Photoshop CS5. After the exclusion of samples with factors which could impair the quality of images and the accuracy of values, a high correlation was demonstrated between age and MGV in samples. A linear regression model (AGE = 173.425-0.755*aveMGV) was established for age prediction, with its performance evaluated using both samples from the training set and the blind test set, in which a mean absolute deviation of 4.42 years and 3.57 years was obtained, respectively. Altogether, MGV could be reckoned as a precise quantification of pigmentation in costal cartilage and an excellent indicator of age prediction in the age interval from 20 to 60 years. Moreover, our strategy appears more user-friendly and accurate, thus exceedingly practical for age estimation in forensic anthropology.

Radiographic evaluation of dental and cervical vertebral development for age estimation in a young Brazilian population

Age estimation is guided by the evaluation of events that happen during the processes of bone and dental development. The purpose of this study was to validate the method of age estimation proposed by Lajolo et al. (2013) through oro-cervical radiographic indices in Brazilians. The study aimed to verify the effectiveness of age estimation equations through dental and cervical vertebrae examinations, in addition to including dental and cervical vertebrae data in new age estimation equations. The sample consisted of panoramic radiographs and teleradiographs from 510 subjects (8-24.9 years). Age estimation methods were applied by assessing the development of seven mandibular teeth, cervical vertebrae and third molars. Techniques used previously have been combinations of radiographic indices: Oro-Cervical Radiographic Simplified Score (OCRSS) and Oro-Cervical Radiographic Simplified Score without Wisdom Teeth (OCRSSWWT). In the second phase of the study, dental maturation, vertebral measurements, and real age were estimated by regression equations. OCRSS and OCRSSWWT had success rates of 67.4% (R2=0.64) and 70.8% (R2=0.62), respectively. When age estimation equations for tooth evaluations were applied, the average error was 1.3 years, and for cervical vertebrae measurements, the error was 1.9 years. When dental variables and the measurements of cervical vertebrae were included, the average error of equations was 1.0 year. Radiographic indices were easy to perform, and after adequate training, are reliable and can be used in forensic practice. The use of the new equations presented in this study is recommended because including cervical vertebrae and dental data provides greater accuracy for age estimation.

A validation study of the Stoyanova et al. method (2017) for age-at-death estimation quantifying the 3D pubic symphyseal surface of adult males of European populations

The age-at-death estimation thresholds have recently been shifted towards a more objective assessment of the aging process. Such a non-subjective approach offers quantitative methods of age estimation; for instance, the method relating to the surfaces of pubic symphyses of males published by Stoyanova et al. (J Forensic Sci 62:1434-1444, 2017). A validation study was conducted to test the method performance in European samples. The sample consisted of 96 meshes of pubic symphyses of male individuals (known sex and age) that came from four different samples (two Portuguese collections, one Swiss, and one Crete). Stoyanova's method based on five regression models (three univariate and two multivariate models) performed worse in our sample, but only when the whole sample (without age limitation) was included. A sample limited to individuals under 40 years of age achieved better results in our study. The best results were reached through the thin plate spline algorithm (TPS/BE) with a root mean square error of 5.93 years and inaccuracy of 4.47 years. Generally, the multivariate regression models did not contribute to better age estimation. In our sample in all age categories, age was systematically underestimated. The quantitative method tested in this study works best for individuals under 40 years of age and provides a suitable basis for further research.

DXAGE: A New Method for Age at Death Estimation Based on Femoral Bone Mineral Density and Artificial Neural Networks

Age at death estimation in adult skeletons is hampered, among others, by the unremarkable correlation of bone estimators with chronological age, implementation of inappropriate statistical techniques, observer error, and skeletal incompleteness or destruction. Therefore, it is beneficial to consider alternative methods to assess age at death in adult skeletons. The decrease in bone mineral density with age was explored to generate a method to assess age at death in human remains. A connectionist computational approach, artificial neural networks, was employed to model femur densitometry data gathered in 100 female individuals from the Coimbra Identified Skeletal Collection. Bone mineral density declines consistently with age and the method performs appropriately, with mean absolute differences between known and predicted age ranging from 9.19 to 13.49 years. The proposed method-DXAGE-was implemented online to streamline age estimation. This preliminary study highlights the value of densitometry to assess age at death in human remains.

Leprosy in a Lombard-Avar cemetery in central Italy (Campochiaro, Molise, 6th-8th century AD): ancient DNA evidence and demography

BACKGROUND

The study of past infectious diseases increases knowledge of the presence, impact and spread of pathogens within ancient populations.

AIM

Polymerase chain reaction (PCR) was used to examine bones for the presence of Mycobacterium leprae ancient DNA (aDNA) as, even when leprosy is present, bony changes are not always pathognomonic of the disease. This study also examined the demographic profile of this population and compared it with two other populations to investigate any changes in mortality trends between different infectious diseases and between the pre-antibiotic and antibiotic eras.

SUBJECTS AND METHODS

The individuals were from a site in Central Italy (6th-8th CE) and were examined for the presence of Mycobacterium leprae aDNA. In addition, an abridged life mortality table was constructed.

RESULTS

Two individuals had typical leprosy palaeopathology, and one was positive for Mycobacterium leprae aDNA. However, the demographic profile shows a mortality curve similar to that of the standard, in contrast to a population that had been subjected to bubonic plague.

CONCLUSIONS

This study shows that, in the historical population with leprosy, the risk factors for health seem to be constant and distributed across all age classes, similar to what is found today in the antibiotic era. There were no peaks of mortality equivalent to those found in fatal diseases such as the plague, probably due to the long clinical course of leprosy.

Geometric morphometric analysis reveals age-related differences in the distal femur of Europeans

Background

Few studies have looked into age-related variations in femur shape. We hypothesized that three-dimensional (3D) geometric morphometric analysis of the distal femur would reveal age-related differences. The purpose of this study was to show that differences in distal femur shape related to age could be identified, visualized, and quantified using three-dimensional (3D) geometric morphometric analysis.

Methods

Geometric morphometric analysis was carried out on CT scans of the distal femur of 256 subjects living in the south of France. Ten landmarks were defined on 3D reconstructions of the distal femur. Both traditional metric and geometric morphometric analyses were carried out on these bone reconstructions. These analyses were used to identify trends in bone shape in various age-based subgroups (<40, 40–60, >60).

Results

Only the average bone shape of the < 40-year subgroup was statistically different from that of the other two groups. When the population was divided into two subgroups using 40 years of age as a threshold, the subject's age was correctly assigned 80% of the time.

Discussion

Age-related differences are present in this bone segment. This reliable, accurate method could be used for virtual autopsy and to perform diachronic and interethnic comparisons. Moreover, this study provides updated morphometric data for a modern population in the south of France.

Conclusion

Manufacturers of knee replacement implants will have to adapt their prosthesis models as the population evolves over time.

A Bayesian Approach to Age-at-Death Estimation from Osteoarthritis of the Shoulder in Modern North Americans

Osteoarthritis (OA) is a marker of degeneration within the skeleton, frequently associated with age. This study quantifies the correlation between OA and age-at-death and investigates the utility of shoulder OA as a forensic age indicator using a modern North American sample of 206 individuals. Lipping, surface porosity, osteophyte formation, eburnation, and percentage of joint surface affected were recorded on an ordinal scale and summed to create composite scores that were assigned a specific phase. Spearman's correlation indicated a positive relationship between each composite score and age (right shoulder = 0.752; left shoulder = 0.734). Transition analysis revealed a tendency toward earlier degeneration of the right shoulder. Bayesian statistics generated phase-related age estimates based on highest posterior density regions. Best age estimates were into the seventh decade at the 90th and 50th percentile. The proposed method supplements traditional techniques by providing age estimates beyond a homogenous 50+ age cohort.