Estimating age of Brazilians using the methods of Demirjian and Nicodemo, Moraes and Médici: A comparative analysis

Abstract

This study proposed to evaluate the precision of Nicodemo, Moraes and Médici method and the method proposed by Demirjian and compare both methodologies in relation to the efficiency and applicability in the Brazilian population. The sample consisted of 124 panoramic radiographs of subjects in the age group from 7 to 16 years old, 66 patients female and 58 male. For the comparison of the genders in relation to the average percentage difference, the t-Student test was considered. In average the method of Nicodemo, Moraes and Médici presented for the female gender an estimated result 14.7% lower than the real age. For the male gender the estimative obtained was that for each year of variation of the real age the method of Nicodemo estimates a variation of 0.48 years, with a confidence interval of 95% given by (0.43; 0.54). For the method of Demirjian the result was that for each year of variation of the real age the method of Demirjian estimates a variation of 1.00 year, with a confidence interval of 95% given by (0.85; 1.15) for the male gender and 0.96 years, with a confidence interval of 95% given by (0.84; 1.08) for the female gender. It is concluded that the Method of Nicodemo, Moraes and Médici tends to underestimate the real age and that as the real age increases this underestimate becomes higher. Now, the method of Demirjian tends to over- estimate the real age in 8.2 months for the male gender and in 7.1 for the female one in average.