Age estimation using postmortem computed tomography-based Hounsfield unit values of the palate and mandibular condyle and the Eichner classification

Shoken Suzuki; Maki Ohtani; Yuhei Matsuo; Masayuki Fukuda; Sohtaro Mimasaka

doi:10.1016/j.legalmed.2024.102446

Age estimation using postmortem computed tomography-based Hounsfield unit values of the palate and mandibular condyle and the Eichner classification

Leg Med (Tokyo). 2024 Apr 16:69:102446. doi: 10.1016/j.legalmed.2024.102446. Online ahead of print.

Authors

Shoken Suzuki¹, Maki Ohtani², Yuhei Matsuo³, Masayuki Fukuda⁴, Sohtaro Mimasaka⁵

Affiliations

¹ Department of Forensic Sciences, Akita University Graduate School of Medicine, Akita, Japan; Department of Dentistry and Oral Surgery, Akita University Graduate School of Medicine, Akita, Japan. Electronic address: shoken.suzuki1@gmail.com.
² Department of Forensic Sciences, Akita University Graduate School of Medicine, Akita, Japan. Electronic address: mohtani@doc.med.akita-u.ac.jp.
³ Department of Forensic Sciences, Akita University Graduate School of Medicine, Akita, Japan. Electronic address: y.matsuo@gipc.akita-u.ac.jp.
⁴ Department of Dentistry and Oral Surgery, Akita University Graduate School of Medicine, Akita, Japan. Electronic address: fukuda@med.akita-u.ac.jp.
⁵ Department of Forensic Sciences, Akita University Graduate School of Medicine, Akita, Japan; Division of Forensic Medicine, Tohoku University Graduate School of Medicine, Sendai, Japan. Electronic address: sohtaro.mimasaka.a8@tohoku.ac.jp.

PMID: 38640872
DOI: 10.1016/j.legalmed.2024.102446

Abstract

Age estimation is important in forensic investigations of unidentified human remains. This study assessed the correlation between age and Hounsfield unit (HU) values of the palate and mandibular condyle based on postmortem computed tomography (CT) and analyzed the influence of occlusal support in developing an age estimation method for Japanese individuals, including older adults. The sample consisted of a training dataset (357 cadavers) and a validation dataset (300 cadavers) that underwent postmortem CT. Three measurements were selected: the respective HU values of the palate and mandibular condyle and the Eichner classification. The correlation coefficients between age and HU values were also evaluated. Multiple stepwise regression analysis was performed to evaluate the significance of four parameters (sex, respective HU values of the palate and mandibular condyle, and the Eichner classification) for age estimation and to determine the best age estimation formula. In the validation tests, inaccuracy and bias were calculated for the groups aged ≥65 or <65 years. Significant correlations between age and HU values of the palate and mandibular condyle were observed, regardless of sex. In multiple stepwise regression analysis, all variables except sex were significantly correlated with age. The age estimation formula from the regression analysis was useful, and the validation test exhibited high accuracy, especially in older adults. The HU values of the palate and mandibular condyle and the Eichner classification are useful for age estimation in Japanese individuals.

Keywords: Age estimation; Eichner classification; Hounsfield unit (HU) values; Mandibular condyle; Palate; Postmortem computed tomography.