3D-3D dentition superimposition for individual identification: A study of an Eastern Chinese population

De-Min Huo; Xiao-Yan Mao; Wei-Wei Mo; Fei-Ming Zhao; Meng Du; Rong-Rong Sun

doi:10.1016/j.forsciint.2023.111801

³D-³D dentition superimposition for individual identification: A study of an Eastern Chinese population

Forensic Sci Int. 2023 Sep:350:111801. doi: 10.1016/j.forsciint.2023.111801. Epub 2023 Jul 27.

Authors

De-Min Huo¹, Xiao-Yan Mao², Wei-Wei Mo³, Fei-Ming Zhao⁴, Meng Du¹, Rong-Rong Sun⁵

Affiliations

¹ Shanghai Key Laboratory of Forensic Medicine, Key Laboratory of Forensic Science, Ministry of Justice, Shanghai 200063, China; Institute of Criminal Science and Technology, Jiading Branch of Shanghai Public Security Bureau, Shanghai 201822, China.
² Department of Orthodontics, Shanghai Jiading District Dental Research Institute, Shanghai 201800, China.
³ School of Mechanical and Power Engineering, East China University of Science and Technology, Shanghai 201424, China.
⁴ School of Maritime Economics and Management of Dalian Maritime University, Dalian 116026, China.
⁵ Department of Orthodontics, School & Hospital of Stomatology, Tongji University, Shanghai Engineering Research Center of Tooth Restoration and Regeneration, Shanghai 200072, China. Electronic address: sunrongrong@tongji.edu.cn.

PMID: 37536075
DOI: 10.1016/j.forsciint.2023.111801

Abstract

Recently, 3D dental intraoral scanning technology has been developed rapidly and applied widely in everyday dental practice. Since 3D dental scanning could provide valuable personal information, it enabled researchers to develop novel procedures for individual identification through ³D-³D dentition superimposition. This study aimed to test the applicability of this method in an Eastern Chinese population and propose a threshold for personal identification. For this purpose, 40 volunteers were recruited, and the initial 80 (upper and lower) 3D intraoral scans (IOS) were collected. After one year, 80 IOS of these volunteers were repeatedly collected. In addition, the other 120 IOS of 60 patients were extracted from the database. The 3D models were trimmed, aligned, and superimposed via Geomagic Control X software, and then the root mean square (RMS) value of point-to-point distance between the two models was calculated. The superimposition of two IOS belonging to the same individual was considered as a match, and superimposition of two IOS belonging to different individuals was considered as a mismatch. Totally, superimpositions of 80 matches and 3120 mismatches were obtained. Intra- and inter-observer errors were assessed through the calculation of relative technical error of measurement (rTEM). Mann-Whitney U test verified possible statistically significant differences between matches and mismatches (P < 0.05). The rTEM of intra- and inter-observer repeatability analyses was lower than 4.7 %. The range of RMS value was 0.05-0.18 mm in matches and 0.72-2.28 mm in mismatches without overlapping. The percentage of accurate identification reached 100 % in blind test through an arbitrary RMS threshold of 0.45 mm. The results indicated that individual identification through the ³D-³D dentition superimposition was effective in Eastern Chinese population. Successful identification could be achieved with high probability when the RMS value of the point-to-point distance of two dentitions is <0.45 mm.

Keywords: (3)D–(3)D dentition superimposition; Forensic odontology; Individual identification; Intraoral scans.

MeSH terms

Asian People
Dentition*
East Asian People
Humans
Imaging, Three-Dimensional* / methods
Software