Estimation of sex based on postcranial elements in European American and Latin American populations.

This study assesses the use of postcranial elements for sex estimation taking population variability into account. European American and Latin American populations are independently analyzed. Nine measurements from postcranial elements were collected from 72 European American individuals, and 59 Latin American individuals. Statistical analyses were performed using the Statistical Package for Social Science (SPSS) version 15. Statistical analyses were conducted to corroborate that there were no intra- or interobserver errors. In both populations, significant differences were found on all measured traits between males and females, except Scapular Breadth in Latin Americans. According to Discriminant Function Analysis (DFA) in the European American population the Ulna Minimum Breadth of the Olecranon (UMBO) correctly classified 91.3% of individuals. When this parameter was combined with the Diameter of Humeral Head (HHD), the two correctly classified 98% of individuals. In Latin Americans, the UMBO correctly classified 82.4% of the individuals. When combined with HHD, the measurements correctly classified 79.4% individuals. UMBO is the most useful trait to correctly assign the sex of the remains in both populations. Including the HHD improved accuracy rates in the European American sample. These results are in agreement with previous studies, which named the humerus as one of the potentially useful bones to consider for sex estimation based on its accuracy. Thus, these two anatomical regions could be used alone or in combination with other methodologies for sex estimation, which is particularly important in situations of fragmentary remains and incomplete skeletons.

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.

A review of forensic analysis of dental and maxillofacial skeletal trauma.

Dental and maxillofacial trauma analysis in the forensic context, includes assessment of both living and deceased persons. It is required in all cases where human abuse is suspected and where signs of skeletal trauma are detected in human remains. Skeletal trauma refers to the damage inflicted to bone, teeth and other hard tissues. An accurate analysis of the dental and maxillofacial trauma is achieved by the assessment of the remains by forensic pathologists, anthropologists and odontologists. This paper aims to review dental and maxillofacial skeletal trauma in the scope of forensic science. High-velocity projectile, sharp force, blunt force, and thermal trauma showing different traits in maxillofacial structures are discussed. Regarding non-fatal physical abuse, head and neck are the most frequently injured areas, resulting in fractures, contusions, burns and traumatic dental injuries.

Setting the light conditions for measuring root transparency for age-at-death estimation methods.

Age-at-death estimation is one of the main goals in forensic identification, being an essential parameter to determine the biological profile, narrowing the possibility of identification in cases involving missing persons and unidentified bodies. The study of dental tissues has been long considered as a proper tool for age estimation with several age estimation methods based on them. Dental age estimation methods can be divided into three categories: tooth formation and development, post-formation changes, and histological changes. While tooth formation and growth changes are important for fetal and infant consideration, when the end of dental and skeletal growth is achieved, post-formation or biochemical changes can be applied. Lamendin et al. in J Forensic Sci 37:1373-1379, (1992) developed an adult age estimation method based on root transparency and periodontal recession. The regression formula demonstrated its accuracy of use for 40 to 70-year-old individuals. Later on, Prince and Ubelaker in J Forensic Sci 47(1):107-116, (2002) evaluated the effects of ancestry and sex and incorporated root height into the equation, developing four new regression formulas for males and females of African and European ancestry. Even though root transparency is a key element in the method, the conditions for measuring this element have not been established. The aim of the present study is to set the light conditions measured in lumens that offer greater accuracy when applying the Lamendin et al. method modified by Prince and Ubelaker. The results must be also taken into account in the application of other age estimation methodologies using root transparency to estimate age-at-death.

When forensic odontology met biochemistry: Multidisciplinary approach in forensic human identification.

When human remains are found, the priority of the investigation is to ascertain the identity of the deceased. A positive identification is a key factor in providing closure for the family of the deceased; it is also required to issue the death certificate and therefore, to settle legal affairs. Moreover, it is difficult for any forensic investigation involving human remains to be solved without the determination of an identity. Therefore, personal identification is necessary for social, legal and forensic reasons. In the last thirty years forensic odontology has experienced an important transformation, from primarily involving occasional dental identification into a broader role, contributing to the determination of the biological profile. In the same way, "DNA fingerprinting" has evolved not only in terms of improving its technology, but also in its application beyond the "classical": helping with the estimation of sex, age and ancestry. As these two forensic disciplines have developed independently, their pathways have crossed several times through human identification operations, especially the ones that require a multidisciplinary approach. Thus, the aim of this review is to describe the contributions of both forensic odontology and molecular biology/biochemistry to human identification, demonstrating how a multidisciplinary approach can lead to a better and more efficient identification.

Daily thanatomicrobiome changes in soil as an approach of postmortem interval estimation: An ecological perspective.

Understanding human decomposition is critical for its use in postmortem interval (PMI) estimation, having a significant impact on forensic investigations. In recognition of the need to establish the scientific basis for PMI estimation, several studies on decomposition have been carried out in the last years. The aims of the present study were: (i) to identify soil microbiota communities involved in human decomposition through high-throughput sequencing (HTS) of DNA sequences from the different bacteria, (ii) to monitor quantitatively and qualitatively the decay of such signature species, and (iii) to describe succesional changes in bacterial populations from the early putrefaction state until skeletonization. Three donated individuals to the University of Tennessee FAC were studied. Soil samples around the body were taken from the placement of the donor until advanced decay/dry remains stage. Bacterial DNA extracts were obtained from the samples, HTS techniques were applied and bioinformatic data analysis was performed. The three cadavers showed similar overall successional changes. At the beginning of the decomposition process the soil microbiome consisted of diverse indigenous soil bacterial communities. As decomposition advanced, Firmicutes community abundance increased in the soil during the bloat stage. The growth curve of Firmicutes from human remains can be used to estimate time since death during Tennessee summer conditions.