Validation of the Third Molar Maturation Index (I3M) to assess the legal adult age in the Portuguese population

Abstract

Age estimation is a major step in forensic and legal procedures. Its relevance has been increasing due to growing society issues, such as identification of missing people, crimes against minors or lack of valid identification papers from locals or foreigners. Evaluation of the cut-off value of the Third Molar Maturation Index (I3M) = 0.08 for discriminating minors from adults in the Portuguese population. The left lower third molars were analysed by applying a specific cut-off value of 0.08 determined by Cameriere et al. in 2008. A sample of 778 digital panoramic radiographs of a representative Portuguese sample (442 females and 336 males), in the age range of 12–24 years (mean age 17.7 ± 2.98 years in females and 18.1 ± 3.0 years in males), was retrospectively evaluated. I3M decreased as the real age gradually increased in both sexes. The 0.08 cut-off score was valuable in discriminating adults from minors. According to the pooled results, the accuracy, by means of area under the curve, was 92.8% (95% confidence interval (CI) 91.0–94.6%). The proportion of correctly classified subjects (sensitivity) was 90.7% (95% CI 88.7–92.8%) and the specificity was 94.9% (95% CI 93.3–96.4%). The results show that I3M is a valuable method to differentiate minors from adults in the Portuguese population.

Dental Age Assessment by I2M and I3M: Portuguese Legal Age Thresholds of 12 and 14 Year Olds

“…For the cut-off point for the 14- year-olds, some studies assume I 2M = 0 which is equal to the cut-off point obtained in this study by the binary logistic regression (the only cases in which I 2M < 0.001 were I 2M = 0). Thus, the reliability measures are similar to the ones obtained in those studies ( 2 , 13 , 26 ).…”

Evaluation of Third Molar Maturity Index by Cone Beam Computed Tomography in Legal Age Estimation

“…This cutoff value, which has also been examined in various populations, has demonstrated high sensitivity and specificity. These additional studies have revealed that I 3M might also be used as a practical predictor of age 18 years in European, 3,8,[10][11][12][13][14][15][16][17][18][19][20] African, 7,[21][22][23][24] Asian, 4,25-28 American, 9,[29][30][31][32][33] and Oceanian 34 populations.…”

“…Clinical and radiological examinations play an important role in the accurately estimating the age of living individuals. These procedures often include medical and dental examinations, dental radiography, and radiographic imaging of the left hand or clavicles 2,3 …”

“…It is essential to use noninvasive and highly precise techniques to differentiate between minors and adults 4 . Radiographic dental examination is one of the most reliable scales for estimating chronological age (CA) compared with skeletal system radiographic examination because dental development is less affected by systemic factors 3 . Various radiographic imaging techniques that can be used in forensic dental identification are bitewing films, panoramic, periapical, cephalometric, and lateral oblique radiographs, digital imaging, and advanced imaging techniques 5…”

“…These procedures often include medical and dental examinations, dental radiography, and radiographic imaging of the left hand or clavicles. 2,3 It is essential to use noninvasive and highly precise techniques to differentiate between minors and adults. 4 Radiographic dental examination is one of the most reliable scales for estimating chronological age (CA) compared with skeletal system radiographic examination because dental development is less affected by systemic factors.…”