Validity of different dental age estimation methods in Pakistani orthodontic patients

Abstract

This research aims to evaluate the validity of Demirjian’s (1973), Nolla’s (1960) and Willem’s (2001) methods of dental age (DA) estimation in Pakistani orthodontic patients (8–16.9 years). It also addresses the validity of these methods in determining dental maturity across the gender and compares the difference between original Demirjian tables (based on French-Canadian standards) and Pakistani tables formulated by Sukhia et al. (2012). Orthopantomograms of 403 subjects (males = 176, females = 227) were examined for DA assessment by different methods. Paired t-test and Wilcoxon signed-ranked tests were used to determine significant differences between mean dental and chronological age among different age groups. Correlation between DA and CA were assessed by the Spearman’s correlation (p = ≤0.05). Nolla’s method under-estimated the DA by 1.00 ± 1.54 in males and over-estimated by 0.21 ± 1.64 in females. DA was significantly advanced using Pakistani tables (males = 0.32 ± 1.17, females = 0.38 ± 1.33 years) and Willem’s method (males = 0.31 ± 1.09, females = 0.29 ± 0.48 years). DA correlated better with CA using Pakistani tables compared with the French-Canadian standards. Earlier dental maturation was reported in females compared with males using Demirjian’s and Nolla’s methods. Strong correlations were found between CA and DA according to all methods (p < 0.001). Overall, Willem’s method was identified as the most valid method for DA estimation in the Pakistani sample.