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الملخص: أهداف البحث: قام الباحثون بفحص العديد من خصائص الأسنان لتحديد الاختلافات في شكل الأسنان بين الذكور والإناث في مجموعات سكانية مختلفة. ومع ذلك، لم يتم إجراء أي بحث للتأكد من إزدواج الشكل الجنسي وتطوير نموذج للتنبؤ بالجنس باستخدام نمط الأخاديد وعدد الحدبات ونمط الإطباق في أي مجموعة. وبذلك توصلت هذه الدراسة إلى الفروق الجنسية والقدرة على التنبؤ بالجنس بناء على هذه الخصائص للأسنان العلوية في المجتمع الباكستاني. طرق البحث: تم اختيار 130 قالبا سنيا (65 ذكر و65 أنثى). تم التقاط صور رقمية للسطح الإطباقي للضاحك الأول والثاني والطاحن الأول العلوي باستخدام كاميرا رقمية. تم تسجيل عدد الحدبات، ونمط الأخاديد، والنمط الإطباقي لكل نوع من الأسنان. تم تحليل البيانات باستخدام اختبار ''مربع كاي'' وتحليل الانحدار اللوجستي. النتائج: أظهر نمط الأخاديد والنمط الإطباقي للضاحك الأول والطاحن الأول العلوي تباينا جنسيا كبيرا. كما أظهر عدد الحدبات في الطاحن الأول العلوي فرقا كبيرا ذا دلالة إحصائية بين الذكور والإناث. بلغت دقة التنبؤ بالجنس للعينات التدريبية 76.7%، بينما كانت 70% للعينات الاختبارية. الاستنتاجات: وجد تباين جنسي كبير في نمط الأخاديد والنمط الإطباقي للضاحك الأول والطاحن الأول العلوي، وكذلك في عدد الحدبات للطاحن الأول العلوي. أظهر نموذج التنبؤ دقة جيدة بنسبة 76.7%، وبالتالي يمكن استخدامه للتنبؤ بالجنس في المجتمع الباكستاني. Abstract: Objective: Researchers have examined several dental characteristics to identify differences in tooth morphology between males and females in various populations. Nevertheless, no research has been undertaken to ascertain sexual dimorphism and develop a sex prediction model by using the groove pattern, cusp number and occlusal pattern in any population group. Therefore, this study accessed the sexual differences and the ability to predict sex according to these characteristics of maxillary teeth in the Pakistani community. Method: A total of 130 dental casts were selected (65 each from males and females). Digital images of the occlusal surface of the maxillary first premolar, second premolar and first molar were captured with a Canon Powershot A2200 14.1 MP digital camera with 4× optical zoom. Cusp number, groove pattern and occlusal pattern were recorded for each tooth type. Data were analysed with chi-square tests and logistic regression analysis. Results: The groove pattern and occlusal pattern of the maxillary first premolar and first molar showed significant sexual dimorphism (p

Estimation of sex is an essential parameter which helps in establishing the biological profile of the deceased in forensic and archaeological examinations. There are two types of methods useful in the estimation of sex –morphological and morphometric. While morphological analysis is subjective and involves visual inspection of the dimorphic traits, morphometric analysis involves statistical analysis and comparison of the measurements to develop a probabilistic estimation of sex. Most studies estimate sex using Discriminant Function Analysis (DFA) that has many restrictive conditions, however, the logistic regression does not have these restrictions and is suitable for a two class problem like estimation of sex.In the present investigation, an attempt has been made to estimate sex by developing logistic regression equations using a cross-sectional sample of 344 young adults (172 females and 172 males). Eight anthropometric measurements were taken on the participants with standard procedures. Hand breadth shows the highest sexual dimorphism and is the best classifier of sex, followed by foot length and hand length. A combined regression model using these three variables has also been proposed that can correctly classify sex with an accuracy of 90.1 % and 91.3 % for males and females, respectively. The likelihood ratio is calculated from the normal probability density curve constructed from the mean and standard deviation for various predictors obtained for the population. It has been concluded that the likelihood ratios corroborate the classification well and the likelihood ratio with its threshold at '1′ can be used as a classifier when there are only two classes. The performance of the likelihood ratio classifier in the present study has been found to be equal to the logistic regression classifier.

Short Tandem Repeat (STR) genotyping is currently the primary DNA-based method for human identification, however it can have limited success when applied to degraded human remains. Massively parallel sequencing (MPS) provides new opportunities to obtain genetic data for hundreds of loci in a single assay with higher success from degraded samples. However, due to the extra requirement for specialised equipment, expertise and resources, routine use of MPS may not be feasible or necessary for many forensic cases. Here we describe the development of a mini-multiplex SNaPshot screening tool (Miniplex) for human samples which allows the qualitative comparison of short mitochondrial and nuclear DNA targets, as well as the interrogation of biogeographic ancestry, lineage, and phenotype single nucleotide polymorphisms (SNPs). This tool is useful to triage samples based on sample quality prior to downstream identification workflows and provides broad biological profile data for intelligence purposes., (Copyright © 2018 Elsevier B.V. All rights reserved.)

Objective: It has been suggested that the level of sexual dimorphism in deciduous dentition is relatively lower than that in permanent dentition. However, in sub adult skeletal remains whose osseous morphological traits of the sex have not defined yet, predicting sex on the basis of odontometric features may be the most precise technique. The aim of the present study was to assess the degree of sexual dimorphism in marginal enamel, dentin and pulp dimensions of second molar deciduous teeth in a pediatric population., Method and Materials: The present study was conducted on bitewing radiographs of 64 males and 60 females. The greatest width of enamel, dentin and pulp on mandibular and maxillary second molar deciduous teeth were measured. Student's t-test and discriminant analysis were used to compare the differences in the odontometric parameters between females and males., Results: Among the second molar measurements, only the maxillary pulp width did significantly discriminate the sex groups. The accuracy of sex identification of a case based on deciduous second molar tooth was approximately 68%., Conclusions: The application of second molar deciduous teeth in sex prediction showed moderate level of sexual dimorphism. In this respect, the maxillary pulp width had the greatest amount of contribution in sex discrimination. Therefore, these odontometric traits, in conjunction with other skeletal features, can be used as a supplementary sexing tool for gender prediction in forensic anthropology., (Copyright © 2016 Elsevier Ltd and Faculty of Forensic and Legal Medicine. All rights reserved.)