OBJECTIVE: Developing teeth are used to assess maturity and estimate age in a number of disciplines. The aim of this study was to determine the accuracy of Demirjian method (Panoramic radiographs were examined and seven mandibular teeth staged according to Demirjian's dental maturity scale) in the forensic clinical medicine. METHODS: Tooth formation was assessed with orthopantomographs in healthy children in dental teaching hospital. There were total 828 children, with 279 boys and 549 girls, aged from 11 to 19 years. The difference between dental and real age was compared and measured, using t-test. RESULTS: The Demirjian method overestimated age in the aged 11-16 years group and had limitations in aged group over 17 years. CONCLUSION: The 95% confidence interval of the mean was least for mean of all developing teeth using Demirjian method (age 11-16 years).