Mastoid and Opisthion-Bimastoid Triangles for Sex Determination in a Brazilian Sample

Abstract

Human identification involving mutilation, advanced decomposition, and skeletonized materials is a challenge for professionals in forensic medicine and dentistry. This study was aimed at a morphometric analysis of the mastoid and bimastoid triangles to determine sex in a Brazilian population. The sample included 80 human skulls (34 females and 46 males; age: 18 to 60 years) from individuals with death certificates. Linear measurements (mm) of the mastoid process -right (n=3) and left (n=3) -and the opisthionbimastoid (n=3) triangles were taken (digital caliper) by two previously trained researchers. Three cranial points -asterion, porion and process -were determined for the right and left mastoid triangle and three others -(1) opisthion and (2) right and (3) left mastoidfor the bimastoid triangle. Heron's formula was used to calculate the area of the triangles assessed. Data were submitted to the Shapiro-Wilk normality test, followed by the unpaired Student's t test or the Mann-Whitney U test, depending on the data distribution verified in the normality test (GraphPad Prism 5.01; p<0.05). The ROC curve was used to measure the accuracy of the variables toward sex determination. The opisthion-bimastoid triangle showed high accuracy and significant differences in all the variables assessed and thus was considered a potential element for sex determination in the Brazilian population assessed.

The Identified Osteological Collections of South America and Their Ethical Dimensions

“…Moreover, five academic dissertations are currently being conducted on this material (Soriano, personal communication). The Biobank Eduardo Daruge produced over 10 papers already published [72][73][74][75][76][77][78][79][80][81][82]. Moreover, very recently, unprecedented results about the lag time of modern bomb-pulse radiocarbon in human bone tissues of a joint project between Brazilian and US researchers were published [43], and the samples used came from the three major Brazilian collections.…”