title: Postmortem CT morphometry with a proposal of novel parameters for sex discrimination of the mandible using Japanese adult data.
abstract: Major human sex differences in the mandible after adolescence include the overall size as well as the shape of the chin and mandibular angle; however, objective interpretation of discrimination accuracy is difficult for these morphological indicators. The present study investigated measurements of the mandible for sex discrimination using postmortem CT morphometry in forensic autopsy cases of Japanese subjects after adolescence (age>16 years; male, n=116, and female, n=106), including the proposal of novel parameters representing the overall mandibular size and shape. The distance between the gnathion and condylus (gn-cdl), and bigonial width (go-go), as well as the angle formed by bilateral gn-cdl lines (Agn-cdl), correlated with bicondylar breadth (cdl-cdl), independent of the body height, showing no significant sex difference. The distance from the gn to the cdl-cdl line (oblique length), the ratio of Agn-cdl to cdl-cdl, and the oblique triangular area formed by bilateral gn-cdl and cdl-cdl lines (Δobl), which were proposed as indicators of chin protrusion, showed significant sex differences (p<0.001). Overall sensitivity and specificity at respective discriminating points for sex estimation were 0.72 and 0.78 at 105.0mm for the oblique length, 0.73 and 0.83 at 0.49 for the Agn-cdl to cdl-cdl ratio, and 0.82 and 0.78 at 643 mm(2) for Δobl; the efficacy for females was greater in younger subjects. Although these parameters weakly depended on the body height (p<0.0001), the correlations were insufficient for stature estimation. These findings suggest the efficacy of CT morphometry of the mandible for sex discrimination with quantitative assessment.
authors.affiliation: Department of Legal Medicine, Osaka City University Medical School, Asahi-machi 1-4-3, Abeno, Osaka 545-8585, Japan.
authors.forename: Tetsuya
authors.initials: T
authors.lastname: Kano
authors.affiliation: Department of Legal Medicine, Osaka City University Medical School, Asahi-machi 1-4-3, Abeno, Osaka 545-8585, Japan.
authors.forename: Shigeki
authors.initials: S
authors.lastname: Oritani
authors.affiliation: Department of Legal Medicine, Osaka City University Medical School, Asahi-machi 1-4-3, Abeno, Osaka 545-8585, Japan; Forensic Autopsy Section, Medico-legal Consultation and Postmortem Investigation Support Center, Department of Legal Medicine, Osaka City University Medical School, Asahi-machi 1-4-3, Abeno, Osaka 545-8585, Japan. Electronic address: michi.leg@med.osaka-cu.ac.jp.
authors.forename: Tomomi
authors.initials: T
authors.lastname: Michiue
authors.affiliation: Department of Legal Medicine, Osaka City University Medical School, Asahi-machi 1-4-3, Abeno, Osaka 545-8585, Japan; Forensic Autopsy Section, Medico-legal Consultation and Postmortem Investigation Support Center, Department of Legal Medicine, Osaka City University Medical School, Asahi-machi 1-4-3, Abeno, Osaka 545-8585, Japan; Division of Forensic Medicine, Faculty of Medicine, Tottori University, 86 Nishi-cho, Yonago, Tottori 683-8503, Japan.
authors.forename: Takaki
authors.initials: T
authors.lastname: Ishikawa
authors.affiliation: Department of Legal Medicine, Osaka City University Medical School, Asahi-machi 1-4-3, Abeno, Osaka 545-8585, Japan; Department of Forensic Medicine & Clinical Toxicology, Faculty of Medicine, Minia University, 61111 Minia, Egypt.
authors.forename: Asmaa Mohammed
authors.initials: AM
authors.lastname: Hishmat
authors.affiliation: Department of Legal Medicine, Osaka City University Medical School, Asahi-machi 1-4-3, Abeno, Osaka 545-8585, Japan; Forensic Autopsy Section, Medico-legal Consultation and Postmortem Investigation Support Center, Department of Legal Medicine, Osaka City University Medical School, Asahi-machi 1-4-3, Abeno, Osaka 545-8585, Japan.
authors.forename: Nozomi
authors.initials: N
authors.lastname: Sogawa
authors.affiliation: Department of Legal Medicine, Osaka City University Medical School, Asahi-machi 1-4-3, Abeno, Osaka 545-8585, Japan; Forensic Autopsy Section, Medico-legal Consultation and Postmortem Investigation Support Center, Department of Legal Medicine, Osaka City University Medical School, Asahi-machi 1-4-3, Abeno, Osaka 545-8585, Japan.
authors.forename: Osamu
authors.initials: O
authors.lastname: Inamori-Kawamoto
authors.affiliation: Department of Legal Medicine, Osaka City University Medical School, Asahi-machi 1-4-3, Abeno, Osaka 545-8585, Japan; Forensic Autopsy Section, Medico-legal Consultation and Postmortem Investigation Support Center, Department of Legal Medicine, Osaka City University Medical School, Asahi-machi 1-4-3, Abeno, Osaka 545-8585, Japan.
authors.forename: Hitoshi
authors.initials: H
authors.lastname: Maeda
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D044466:Asian People; D001344:Autopsy; D005260:Female; D006801:Humans; D008297:Male; D008334:Mandible / Q000033:anatomy & histology*; D008875:Middle Aged; D012680:Sensitivity and Specificity; D012732:Sex Determination Analysis / Q000379:methods*; D012737:Sex Factors; D014057:Tomography, X-Ray Computed / Q000379:methods*
keywords: Forensic anthropology; Japanese; Mandible; Sex discrimination; Skeletal development