Age-at-death estimation in older adults is complicated because current techniques fail to capture an older individual’s age-at-death in a narrow enough range. This study aimed to test the relationship between osteoporotic change and age-at-death in the form of intracortical porosity. It was hypothesized that as individuals age, osteoporotic processes increase resulting in a higher percentage of intracortical porosity that may correlate with particular age cohorts. Forty ribs were analyzed, ranging in age from 15 to 84. Ribs sections were digitized using a 40X objective on a Nikon E600 microscope equipped with a motorized stage and a Turboscan montaging system (Objective Imaging Inc., UK). Images were made binary using image ImageJ 2.0. Nine measurements and calculations as described by the Agnew and Stout (2012) method were used: total subperiosteal area, endosteal area, cortical area, percent cortical area (%C/T), porosity area, percent porosity area, absolute cortical area, percent absolute cortical area (%CA/T), and the difference between %C/T and %CA/T. The ranges and mean values for intracortical porosity across the sample were calculated. The effect of intracortical porosity on measures of cortical area were interpreted using a calculation of the difference between %C/T and %CA/T. A Two Sample Independent T-Test was performed to see if there was a significant difference between sexes. Regression analyses were conducted to assess correlations between the traits and age-at-death. No significant difference was found between sexes in regards to intracortical porosity or the difference between %C/T and %CA/T. The mean intracortical porosity was found to be 15.30. The mean value of the difference was found to be 6.95%. Measures of intracortical porosity varied from 0.74% - 31.67% while measures of the effect of intracortical porosity varied from 0.32% - 17.85%. No correlation was found between either trait and age-at-death. There are a number of reasons intracortical porosity might not be correlated with an individual’s age-at-death including (1) processes that influence intracortical porosity, (2) hormonal changes, (3) the current understanding of the relationship between aging and bone cell functions. One should still account for intracortical porosity when conducting histomorphometric analyses, as failure to consider it would result in miscalculations.

Magister Scientiae Dentium - MSc(Dent) / A number of dental age estimation methods have been developed over the years ranging from the frequently used age estimation of Demirjian et al (1973) and Moorrees et al (1965) to the less frequently used age estimation methods of Haavikko (1970) and Nolla (1960). Different dental age estimation methods have been used with variable success. These were developed using mainly children of Central and Northern European descent and white North Americans. The results of the above-mentioned dental age estimation methods, when used on South African children, show that the need for adaptation of these methods exists. Phillips has thus developed a dental age estimation table for Nguni children of South Africa, to assist in correcting this discrepancy. OBJECTIVE: To establish if the Phillips dental age estimation developed for Nguni children of South Africa is applicable to children in the region of Mpumalanga. METHOD: Cross sectional study using a stratified random sampling method involving 100 panoramic radiographs of black children up to the age of 14 years, in the region of Mpumalanga. CONCLUSION: This study will determine if Phillips dental age estimation tables developed for South African Nguni children is applicable and accurate in estimating the age of black Mpumalanga children.

Estimating sex and age at death are two crucial processes during the creation of a biological profile for a set of skeletal remains. Whether the remains are archaeological or forensic, estimating the sex and age of the individual is necessary for further analysis and interpretation. Specifically, in a medicolegal context, knowing the biological sex and approximate age of the remains assists law enforcement or government agencies in identifying unknown individuals. Since the inception of the field of forensic anthropology, practitioners have been developing methods to perform the aforementioned tasks. It is crucial that these methods be consistent, repeatedly tested, validated, and improved for multiple reasons. Firstly, to conform to Daubert (1993) standards, and additionally, to make sure that they are accurate and applicable to modern forensic cases. The present study was performed to validate the efficacy of the method for estimating sex from the os pubis originally proposed in Klales et al. (2012), as well as the efficacy of the “transition analysis” method for estimating age, originally outlined in Boldsen et al. (2002). Considering the recent popularity of using these methods to create a biological profile for forensic cases, it is necessary to develop error rates on a large, modern, American autopsy sample. These two methods are not only being readily utilized, but are additionally being taught to students in training. The utilization of these models involves a “logistic regression model” created by Klales et. al (2012) to process ordinal scores, and the Bayesian statistics software program “ADBOU” that was created for processing data collected using the method in Boldsen et. al (2002). These statistical systems which produced age estimates are relatively young compared to methods developed for the same purpose. The new generation of forensic anthropologists is fully responsible for objectively critiquing and validating these methods that are being disseminated by their professors and senior practitioners. The goal of the present study is to do just that. A skeletal reference sample of 630 pubic bones, all removed from modern autopsy cases and housed at the Maricopa County Forensic Science Center in Phoenix, Arizona, was utilized for data collection in the present study. Each pubic bone was assessed and scored according to the exact instructions outlined in the materials for each method, which was the Klales et al. (2012) paper for sex estimation, and the UTK Data Collection Procedures for Forensic Skeletal Material 2.0 for age estimation (Langley et al. 2016). Additionally, the observers recorded their “gestalt” estimates for sex using the Phenice (1969) system, as well as Brooks and Suchey (1990) and Hartnett (2010a) phases for each pubis. Demographic information labels were hidden, and the collection demographic information was not viewed until the completion of data collection. The null hypothesis in the present study is that both methods (the Klales et al. method (2012) and “transition analysis” method (Boldsen et al. 2002) will perform as well as they did in the original studies. The alternate hypothesis is that they do not result in the same accuracy rates reported in the original studies. Statistical analysis of the data indicates that there is sufficient evidence to reject the null hypothesis as it applies to the Klales et al. (2012) method. The classification accuracies achieved applying the logistic regression equation to the sample of pubic bones was found to be significantly lower than reported in the original study (86.2%), averaging around 70% between observers. The level of both intraobserver and interobserver agreement was only moderate for this method. It was also found that asymmetry occurred in some individuals, producing differing estimates of sex when the left and right pubes were scored separately. When utilizing the Boldsen et al. (2012) method and the ADBOU software package on only pubic symphyseal components to estimate age, the method was found to perform reasonably well. The majority (about 82%) of individuals had actual ages at death that fell within the predicted range produced by the statistical analysis. The majority of the symphyseal component scores showed moderate to good levels of interobserver agreement, and the estimated maximum likelihood (point estimate) of age at death predicted by the software package correlated moderately well with the actual age of death of the individual. These methods did not perform as well as reported in the original studies, and they should be further validated and recalibrated to improve their accuracy and reliability.

Syftet med föreliggande studie var att undersöka hur bra vi är på att bedöma ålder på omaskerade och maskerade ansikten. Syftet var även att undersöka om det fanns systematiska fel som är förknippade med åldersbedömning av maskerade ansikten. Totalt fick 60 försöksdeltagare, samtliga ungdomar, skatta åldern på 60 fotografier av 30 maskerade och 30 omaskerade män.  Fotografierna var indelade i två åldersgrupper, yngre och äldre, och samtliga stimulipersoner förekom i både den maskerade och den omaskerade varianten. Resultaten visade att försöksdeltagarna var bättre på att skatta åldern på omaskerade ansikten än på maskerade. Inga skillnader i systematiska fel fans mellan maskerade och omaskerade ansikten. Bilder av unga ansikten skattades med högre precision än bilder av äldre ansikten. / The purpose of this study was to investigate how well we are at age estimations of masked and unmasked faces. The purpose was also to investigate if there were any biases that effected age estimations of masked faces. A total of 60 participants, all juveniles, estimated the age of 60 photographs of 30 masked and 30 unmasked men. The photographs were divided into two age groups, younger and older, and all of the men, who served as stimuli, were represented in both conditions. The results showed that the participants were better at estimating the age of unmasked than masked faces. There were no differences in biases between masked and unmasked faces. Photographs of young faces were estimated with greater precision than older faces.

The aim of this study was to test the accuracy of two methods for age estimation in non-adults, Cameriere’s European formula and AlQahtani’s London Atlas, on a multi-ethnic American sample. Radiographs of European, Hispanic and American Indian children (166 girls and 194 boys) aged between 6 and 17 years were analyzed following both methods. The accuracy of each method was assessed using the mean difference and the mean of the absolute values of the residuals (mean prediction error). Categories relating to ethnicity, sex and age were applied to the assessment of accuracy in order to compare these two approaches. Results indicate that Cameriere’s European formula significantly underestimated age for both sexes (p < 0.001), with a mean difference of -1.19 years for girls and -1.32 years for boys, prompting the first author to create an American specific formula. The American formula slightly overestimated age but this difference was not significant (p>0.05). Using Cameriere’s European formula the mean prediction error (ME) was 1.51 years for girls and 1.58 years for boys while the ME was 1.24 years for girls and 1.13 years for boys, using the American formula. The London Atlas underestimated age with a mean difference of -0.18 for girls and -0.16 for boys. The absolute mean difference was 1.04 years for girls and 1 year for boys. For both methods, differences in accuracy based on sex or ethnic group were not significant (P>0.05). The results indicate that both methods may be useful for estimating age in a forensic context.

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The estimation of age is an important aspect in osteoarchaeological analysis. In order to understand people and their fates in past societies, researchers must turn to palaeodemography. Therefore, it is vital that the methods of age estimation, which the foundations of palaeodemographic reconstructions rest upon, are as accurate and reliable as possible. In current Swedish cremation-osteoarchaeology, two methods of age estimation are commonly used: suture closure and relative thickness of the diploë. However, no substantial evaluation of these two methods have been undertaken. This study aims to evaluate the two methods of age estimation of cremated remains, suture closure and relative thickness of the diploë. This was done by testing the two methods on two unburnt populations, Mediaeval city-dwellers from Helgeandsholmen, Stockholm, Sweden, and Middle-Neolithic hunter-gatherers from Ajvide, Gotland, Sweden. Suture closure and proportion of diploë was observed in comparison with age-related changes of the auricular surface of the ilium and the pubic symphysis. Based on the results of the study, possible courses of action were proposed and then applied on cremated remains from a Late Iron Age burial ground on Lovö, Stockholm, Sweden. The results showed significant moderate correlation with age for both methods (0.61 for suture closure and 0.58 for proportion of diploë). However, early stage of suture closure could identify a group consisting of juveniles and young adults, while advanced suture closure could identify a group consisting of middle adults and old adults. These results, which proved to be more reliable than existing methods, can, hopefully, lead to improvements of the assessment of age in cremated remains, and increase our understanding of the fates of people of the past.

Several techniques for estimating adult age-at-death are used in biological and forensic anthropology, including morphological changes of the ribs. However, due to human variation and taphonomic damage, it remains difficult to produce accurate and meaningful age-at-death estimations based on skeletal remains. This research further explores morphological changes to the first rib, which is easily identifiable and relatively robust, including the costal face and tubercle facet identified by Kunos’ (1999) and modified by DiGangi et al. (2009). A total of 400 European American individuals (f=200; m=200) from the William M. Bass Donated Skeletal Collection at the University of Tennessee, Knoxville, were observed using modified descriptions for Kunos’ (1999) five traits of the costal face and tubercle facet, on an ordinal scale of 1-8. Additionally, bone quality was assessed on an ordinal scale of 1-3 and was incorporated as a variable in order to improve estimations. Exploratory statistical analysis demonstrates that all eleven traits correlate with age at a statistically significant level, with bone quality being the most significant feature for both sexes. Female and male differences were found, and cross-validated ordinal logistic regression equations are presented for each. The resulting AIC table estimates 100% of the male and female sample correctly, though the produced ranges are too large to be forensically relevant. The results of this research underscore the importance of developing age estimation methods on skeletal regions that are under researched and for those that are more resistant to taphonomic damage.

The age estimation method as described by Demirjian is the most frequently used tool to estimate the sub-adult dental age in forensic dentistry. This technique has been shown to over or under estimate the chronological age of sub-adults when applied to specific population groups. The aim of this study was to compare a black South African population sample with the original French-Canadian model to determine if Demirjian’s method accurately reflects the true chronological age of this population group. A sample of panoramic radiographs from 279 boys and 325 girls between the ages of 6 and 16 was obtained from the School of Dentistry University of Pretoria, and from orthodontists in private practice in the Pretoria region. The panoramic radiographs were used to score the seven left mandibular teeth. The calculated maturity score was used to determine the Demirjian dental age. All panoramic radiographs were scored by one examiner. A subset of 20 panoramic radiographs was scored by a second examiner and reliability tested using a Wilcoxon Matched Pairs Test. This research showed that black South African children have a more advanced dental age compared to French-Canadian children. Demirjian overestimated the age for boys by 0.8 years and for girls by 0.5 years. The dental age assessment provided by Demirjian is not suitable for black South African children. As a result, new standards of dental age assessment should be established for this population. Copyright / Dissertation (MSc(Odont))--University of Pretoria, 2011. / Oral Pathology and Oral Biology / unrestricted