Sex-specific linear regression models for age estimation using Cameriere’s third Molar Maturity Index (I3M): a preliminary report from Turkiye

Emine Nur Kahraman; Şehrazat Evirgen; Ayşe Gülşahı; Isabella Lima Arrais Ribeiro; Roberto Cameriere

Sex-specific linear regression models for age estimation using Cameriere’s third Molar Maturity Index (I3M): a preliminary report from Turkiye

Abstract

Aims: Cameriere’s Third Molar Maturity Index (I3M) is well established for age-threshold determination, yet its application in regression-based age estimation has not been explored in the Turkish population. This study aimed to derive sex-specific linear regression models for estimating chronological age from I3M in Turkish adolescents and young adults. Methods: This retrospective cross-sectional study evaluated 200 digital panoramic radiographs of individuals aged 14-22 years. I3M was quantified on left mandibular third molars using standardized ImageJ-based measurements by a single blinded examiner (ICC=0.90). Linear regression models were constructed for the pooled sample and separately by sex. Results: I3M showed a statistically significant inverse association with chronological age in all models (p<0.001). In the pooled analysis [age=19.04 - 4.24×I3M; B=-4.24, SE=0.33, 95% CI (-4.88, -3.60)], the model accounted for 46.1% of the variance (adjusted R²=45.9%) with a standard error of estimate (SEE) of 1.65 years and a mean absolute error (MAE) of 1.34 years. Sex-stratified models showed comparable performance: females (R²=49.5%, SEE=1.64, MAE=1.36) and males (R²=41.5%, SEE=1.69, MAE=1.31), with no statistically significant difference between models (Chow test p=0.67). Conclusion: This preliminary study presents the first population-specific regression equations for I3M in Turkiye. These models may serve as a complementary forensic tool for age estimation across multiple legally relevant thresholds. However, the moderate explained variance warrants caution, and external validation in an independent Turkish sample is required before routine forensic application.

Keywords

Ethical Statement

This retrospective cross-sectional study was conducted in adherence to the STROBE (Strengthening the Reporting of Observational Studies in Epidemiology) guidelines 21 and was approved by the Uşak University Research Ethics Committee (Approval No: 08, Date: 05.05.2021). Written informed consent was obtained from the parents or legal guardians of all participants at the time of radiographic imaging. All data were anonymized before analysis.

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Details

Primary Language

English

Subjects

Forensic Dentistry

Journal Section

Research Article

Authors

Emine Nur Kahraman ^*
0000-0001-9942-8303
Türkiye

Şehrazat Evirgen
0000-0001-5760-0531
Türkiye

Ayşe Gülşahı
0000-0003-1990-1637
Türkiye

Isabella Lima Arrais Ribeiro
0000-0001-6538-6811
Brazil

Roberto Cameriere
0000-0002-3775-2244
Italy

Publication Date

May 19, 2026

Submission Date

January 21, 2026

Acceptance Date

April 4, 2026

Published in Issue

Year 2026 Volume: 9 Number: 3

IZ

https://izlik.org/JA69AL52DW

Cite

RIS / Bibtex

APA

Kahraman, E. N., Evirgen, Ş., Gülşahı, A., Arrais Ribeiro, I. L., & Cameriere, R. (2026). Sex-specific linear regression models for age estimation using Cameriere’s third Molar Maturity Index (I3M): a preliminary report from Turkiye. Journal of Health Sciences and Medicine, 9(3), 621-626. https://izlik.org/JA69AL52DW

AMA

1.Kahraman EN, Evirgen Ş, Gülşahı A, Arrais Ribeiro IL, Cameriere R. Sex-specific linear regression models for age estimation using Cameriere’s third Molar Maturity Index (I3M): a preliminary report from Turkiye. J Health Sci Med / JHSM. 2026;9(3):621-626. https://izlik.org/JA69AL52DW

Chicago

Kahraman, Emine Nur, Şehrazat Evirgen, Ayşe Gülşahı, Isabella Lima Arrais Ribeiro, and Roberto Cameriere. 2026. “Sex-Specific Linear Regression Models for Age Estimation Using Cameriere’s Third Molar Maturity Index (I3M): A Preliminary Report from Turkiye”. Journal of Health Sciences and Medicine 9 (3): 621-26. https://izlik.org/JA69AL52DW.

EndNote

Kahraman EN, Evirgen Ş, Gülşahı A, Arrais Ribeiro IL, Cameriere R (May 1, 2026) Sex-specific linear regression models for age estimation using Cameriere’s third Molar Maturity Index (I3M): a preliminary report from Turkiye. Journal of Health Sciences and Medicine 9 3 621–626.

IEEE

[1]E. N. Kahraman, Ş. Evirgen, A. Gülşahı, I. L. Arrais Ribeiro, and R. Cameriere, “Sex-specific linear regression models for age estimation using Cameriere’s third Molar Maturity Index (I3M): a preliminary report from Turkiye”, J Health Sci Med / JHSM, vol. 9, no. 3, pp. 621–626, May 2026, [Online]. Available: https://izlik.org/JA69AL52DW

ISNAD

Kahraman, Emine Nur - Evirgen, Şehrazat - Gülşahı, Ayşe - Arrais Ribeiro, Isabella Lima - Cameriere, Roberto. “Sex-Specific Linear Regression Models for Age Estimation Using Cameriere’s Third Molar Maturity Index (I3M): A Preliminary Report from Turkiye”. Journal of Health Sciences and Medicine 9/3 (May 1, 2026): 621-626. https://izlik.org/JA69AL52DW.

JAMA

1.Kahraman EN, Evirgen Ş, Gülşahı A, Arrais Ribeiro IL, Cameriere R. Sex-specific linear regression models for age estimation using Cameriere’s third Molar Maturity Index (I3M): a preliminary report from Turkiye. J Health Sci Med / JHSM. 2026;9:621–626.

MLA

Kahraman, Emine Nur, et al. “Sex-Specific Linear Regression Models for Age Estimation Using Cameriere’s Third Molar Maturity Index (I3M): A Preliminary Report from Turkiye”. Journal of Health Sciences and Medicine, vol. 9, no. 3, May 2026, pp. 621-6, https://izlik.org/JA69AL52DW.

Vancouver

1.Emine Nur Kahraman, Şehrazat Evirgen, Ayşe Gülşahı, Isabella Lima Arrais Ribeiro, Roberto Cameriere. Sex-specific linear regression models for age estimation using Cameriere’s third Molar Maturity Index (I3M): a preliminary report from Turkiye. J Health Sci Med / JHSM [Internet]. 2026 May 1;9(3):621-6. Available from: https://izlik.org/JA69AL52DW