Arash Dabbaghi
Mohammad Kazemi

Background: Age estimation is a fundamental part of forensic science. Considering the fact that pulp size decreases throughout the life because of secondary dentine apposition, many researchers have used it as a method for age estimation with great results. This study aimed to determine the applicability of tooth to pulp ratio in mandibular second premolars in an Iranian population using panoramic radiographs. Methods: The sample consisted of ۱۵۳ digital panoramic images of male and female Iranians aged ۱۳-۷۰ years, and the tooth to pulp ratio of both left and right mandibular second premolars was obtained using AutoCAD software. Analysis of variance (ANOVA), Pearson’s correlation, and regression analysis were used to analyze the data. A total of ۲۰ images were reexamined after ۳۰ days to test intra-observer error. Results: ANOVA test showed that gender had no effect on age estimation, and there was a significant correlation between age and tooth/pulp ratio (r=۰.۶۷۹ for right premolar, r=۰.۷۱۲ for left premolars, and r=۰.۷۳۶ for both premolars). Linear regression formulae were created based on the results and the mean differences between the estimated and actual age were reported to be ۱۰.۳۵±۰.۵۱, ۹.۱۷±۰.۵۴, and ۸.۸۳±۰.۵۲ for right, left, and both premolars, respectively. Intra-observer error showed no significant difference between repeated measurements. Conclusions: Tooth/pulp ratio of mandibular second premolars is a reliable and repeatable method for age estimation in Iranian population and using premolars of both sides yields the best results.