Sex estimation is one of the primary aspects in determining the biological characteristics of an unknown adult skeleton. The variations between male and female skeletons can be attributed to a complex interplay of genetics, hormonal factors, culture, and environment. However, skeletal remains frequently found are often incomplete, with most sexually dimorphic bone like the pelvis and skull potentially absent. Hence, it is essential to conduct a comprehensive evaluation of multiple skeletal elements to attain a high degree of precision in sex estimation within forensic anthropology context. Ribs have been utilized in forensic anthropology for sex estimation since the 1980s, a comprehensive review of their sexual dimorphism is yet to be conducted. In this study, we examined various anthropological methods applied to ribs for sex estimation. Method: A systematic search was performed using PubMed, Science Direct, and Google Scholar from 2000 to 2020, retrieving a total of 10 articles that met the inclusive criteria. The search followed the main points outlined in the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. Results: This systematic review provides a comprehensive summary of the analytical approaches employed to estimate sex using human ribs. Conclusion: The findings revealed that different part of human ribs can be reliably used for sex estimation via metric method.

Background: Age estimation of unidentified human remains is an essential for establishing the biological profile of unidentified human remains. Previous studies have investigated the value linear measurements of the frontal sinus for age estimation while the value of two-dimensional (2D) geometric morphometric measurements have not been explored for this purpose. Objective: This study aims to evaluate the morphological variation of frontal sinus among adults Malaysian for age estimation using 2D geometric morphometric methods. Methods: Lateral skull radiographs of 453 adult Malaysians, comprising 151 young adults (20–39 years old), 150 middle-aged adults (40–59 years old) and 152 old adults (60–79 years old), were retrieved retrospectively. Eight 2D landmarks were applied to digitalized radiographs using TPSDig2 software. 2D geometric morphometric analysis was performed by MorphoJ software. Results: Procrustes ANOVA revealed no significant differences in shape and size (p-value > 0.05) of frontal sinus between the three age groups. However, Canonical Variate Analysis showed significant differences for Mahalanobis and Procrustes distances (p-value < 0.05) between young and old adult groups. Discriminant Function Analysis after cross-validation demonstrated an age classification accuracy of 53.5 %. Conclusion: The study suggests that 2D geometric morphometric analysis of the frontal sinus cannot be reliably used to estimate the age of an unknown Malaysian individual.

Sex determination is the crucial stage for developing a biological profile during the investigation of skeletal remains. An accurate determination of the sex of the unknown person is crucial by only a few bones or when multiple bones are missing or fractured. Thus, exploration of less commonly used bones like thoracic vertebrae is also required for the personal identification of an unknown individual.