Evaluation of Demirjian staging method reproducibility and reliability for dental age estimation between eight forensic experts

Abstract

Assigning a developmental stage is the most subjective step in dental age estimation. Therefore, clear stage definitions and proper observer calibrations are essential or high reliability and reproducibility. In this study, the reliability of the Demirjian method was assessed among 8 experts in DAE. The sample used were panoramic radiographs consisting of 50 healthy patients aged between 15 and 13.99 years old. Seven permanent teeth on the left side in both maxilla and mandible were selected to be examined. Further reference to both reliability and reproducibility will be referred as "reliability". The intra- and inter-rater reliability was assessed using Cohen's Kappa and Gwet's AC1/AC2 value for the overall tooth type, and specific tooth reliability. The intra-rater reliability gives an excellent reliability within observers ranging from 0.86 to 1. The inter-rater reliability was 0.962, with no difference between maxilla (0.950) and mandible region (0.954). Additionally, it was observed that canines and premolars have a lower agreement (0.934) compared to incisors and molars. Further detailed analysis for each tooth gives the lowest reliability to FDI 32 (0.868). Although the Demirjian staging method offers robust reliability for DAE with an emphasis on standardized protocols and examiner calibration, the performance of staging varies across different tooth types.

Keywords: Demirjian method; Dental age estimation; Forensic dentistry; Panoramic radiographs; Reliability.