The digital technology in the industrial era 4.0 has developed very rapidly, including in the field of forensic dentistry. The combination of 3-dimensional (3D) technology with forensic dentistry is able to provide various kinds of information about one’s identity accurately and in detail. Some examples of the application of 3D imaging technology in the field of forensic dentistry are bitemark analysis, individual identification, and dental morphological analysis.
Responding to the challenges of technological development in the field of forensics, researchers from Department of Forensic Odontology, Faculty of Dental Medicine, Universitas Airlangga, Surabaya conducted a research collaboration with the Department of Dental and Digital Forensic Graduate School of Dentistry of Tohoku University and the Department of Computer and Mathematical Sciences of the Graduate School of Information Sciences at Tohoku University, Japan . The research aims to find the most effective part of the arch and surface of human teeth for the benefit of forensic identification using 3D imaging technology. Vivid 910 3D scanner (Konica Minolta, Japan) and Rapidform XOS / SCAN software (INUS Technology, South Korea) are used to retrieve and process 3D models from dental cast to form 3D point clouds. Next, a superimposition of 2 3D point clouds was performed to calculate the magnitude of the difference between the two using the iterative closest point (ICP) algorithm in the Matlab programming language (MathWork Inc., USA).
The magnitude of the difference of each 3D point clouds is determined by calculating the value of the root mean square error (RMSE). Two 3D dental point clouds are said to be similar if the RMSE value is close to 0.0 millimeters. Conversely, the greater the value of RMSE, the greater the difference of them.
The results of this study indicates that to determine the similarities and differences between individuals using a 3D imaging approach requires a minimum of 4 teeth from one human jaw. In addition, it is known that the labial surface (surface of the teeth facing the lips) of the human front teeth is sufficient to determine the similarities and differences in dental arches between individuals.
In the field of forensic odontology, the results of this study can be applied to the case of individual identification where there is difficulty in performing dental examinations on someone who has died and in someone who has a trismus condition. In addition, this method can be used to assist the forensic team in digitally comparing postmortem and antemortem dental conditions quickly and efficiently.
This study has several limitations, such as, the subject of this study is classified as having normal dental arch conditions, so further research still needs to be done to apply this method to the condition of crammed teeth, missing teeth, and dentures in the research subjects.
Author: Arofi Kurniawan, drg., Ph.D.
Details of this article available at:
Arofi Kurniawan, Kouya Yodokawa, Moe Kosaka, Koichi Ito, Keiichi Sasaki, Takafumi Aoki & Toshihiko Suzuki. 2020. Determining the effective number and surfaces of teeth for forensic dental identification through the 3D point cloud data analysis. Egyptian Journal of Forensic Sciences, volume 10, Article number: 3