The chronology of second and third molar development in Koreans and its application to forensic age estimation

The accuracy of forensic age estimation based on the chronology of second (M2) and third molar (M3) development was investigated using 2,087 orthopantomograms of Korean men and women aged between 3 and 23 years. The developmental stages of M2s and M3s in these subjects were classified using the criteria of Demirjian. Inter-observer reliability and statistical data on each stage of mineralization of M2s and M3s were evaluated. The left-right symmetries of the maturation degrees in the M2s and M3s were observed in both sexes, between which no arch differences were found, but statistically significant sex-specific differences were observed in some stages of M2 and M3 development. In multiple regression analysis, a strong positive relationship was observed between age and mineralization of M2s and M3s. The regression formulas for estimating the age of Koreans were presented based on sex and combination of teeth. These results suggest that the developments of second and third molars can be considered as valuable age indicators in Korean adolescents and young adults.