Third molar maturity index (I3M) assessment according to different geographical zones: a large multi-ethnic study sample

• Published in: International journal of legal medicine 2023-03, Vol.137 (2), p.403-425
• Main Authors: Angelakopoulos, Nikolaos, De Luca, Stefano, Oliveira-Santos, Inês, Ribeiro, Isabella Lima Arrais, Bianchi, Ilenia, Balla, Sudheer B., Kis, Hatice Cansu, Jiménez, Lourdes Gómez, Zolotenkova, Galina, Yusof, Mohd Yusmiaidil Putera, Selmanagić, Aida Hadzić, Pandey, Hemlata, Pereira, Palmela C., da Nóbrega, Johnys Berton Medeiros, Kalani, Hettiarachchi, Mieke, Sylvia M., Kumagai, Akiko, Gulsahi, Ayse, Zelić, Ksenija, Marinković, Nemanja, Kelmendi, Jeta, Galić, Ivan, Vázquez, Israel Soriano, Spinas, Enrico, Velezmoro-Montes, Ymelda Wendy, Moukarzel, Maria, Toledo, Jorge Pinares, El-Bakary, Amal Abd El-Salam, Cameriere, Roberto
• Format: Article
• Language: English
• Subjects: Adolescent; Adult; Age; Age Determination by Teeth - methods; Asia; Chronology; Continents; Contingency; Europe; Female; Forensic Medicine; Forensic odontology; Humans; Male; Males; Medical Law; Medicine; Medicine & Public Health; Molar, Third - diagnostic imaging; Original Article; Radiography, Panoramic; Refugees; Teeth
• ISSN: 0937-9827; 1437-1596
• DOI: 10.1007/s00414-022-02930-x

Identification of living undocumented individuals highlights the need for accurate, precise, and reproducible age estimation methods, especially in those cases involving minors. However, when their country of origin is unknown, or it can be only roughly estimated, it is extremely difficult to apply assessment policies, procedures, and practices that are accurate and child-sensitive. The main aim of this research is to optimize the correct classification of adults and minors by establishing new cut-off values for four different continents (Africa, America, Asia, and Europe). For this purpose, a vast sample of 10,701 orthopantomographs (OPTs) from four continents was evaluated. For determination and subsequent validation of the new third molar maturity index ( I 3M ) cut-off values by world regions, a cross-validation by holdout method was used and contingency tables (confusion matrices) were generated. The lower third molar maturity indexes, from both left and right side ( I 3M L and I 3M R ) and the combination of both sides ( I 3M L _ I 3M R ) were calculated. The new cut-off values, that aim to differentiate between a minor and an adult, with more than 74.00% accuracy for all populations were as follows ( I 3M L ; I 3M R ; I 3M L _ I 3M R , respectively): Africa = (0.10; 0.10; 0.10), America = (0.10; 0.09; 0.09), Asia = (0.15; 0.17; 0.14), and Europe = (0.09; 0.09; 0.09). The higher sensitivity (Se) was detected for the I 3M L for male African people (91%) and the higher specificity (Sp) of all the parameters ( I 3M L ; I 3M R ; I 3M L _ I 3M R ) for Europeans both male and female (> 91%). The original cut-off value (0.08) is still useful, especially in discriminating individuals younger than 18 years old which is the goal of the forensic methods used for justice.