Validity and repeatability of the pulp/tooth area ratio for age estimation in adults: A test of the Cameriere et al. methods in a U.S. population

Estimating age as accurately as possible in older adults (50 years and above) remains a challenge. Dental methods such as the pulp/tooth area ratio developed by Cameriere et al. have shown promising results in different populations. However, their applicability across forensic contexts remains underexplored. This study evaluates the repeatability and validity of the Cameriere method in a contemporary U.S. sample using cone-beam computed tomography (CBCT) scans. A total of 136 mandibular canines, 89 first premolars, and 82 second premolars from 146 individuals were analyzed. Intra- and inter-observer reliability were evaluated using technical error of measurement (TEM), relative TEM (rTEM), and intraclass correlation coefficients (ICC). Method accuracy was assessed using mean residuals, mean absolute residuals, and the percentage of individuals within the 95 % prediction interval. The method exhibited overall poor performance: only 46.90–58.33 % of individuals true age fell within the 95 % prediction interval. Performance was inconsistent across different age groups: individuals under 30 and over 60 years of age had greater prediction error. Mean absolute residuals were 13.52 years for the canine, 15.37 years for the first premolar, and 15.03 years for the second premolar. All teeth showed negative mean residuals indicating overall underestimation of the individuals' ages. While tooth area measurements showed acceptable repeatability, pulp cavity measurements exceeded acceptable error thresholds, suggesting observer experience plays a critical role in the application of this method. We discuss the implications of our results for understanding the limitations of this method in forensic casework in the U.S. and other populations.