The applicability of the original and revised Demirjian standards to age estimations of 5-15 year old Indian children.

Background: The Demirjian method has been the most widely tested method for the estimation of the dental age of children and adolescents. However, only three studies have compared Demirjian's original and revised seven-tooth methods, four-tooth method and alternate four-tooth method, none of them conducted on an Indian population.

Aim: The present study aimed to compare the applicability of the original and revised seven-tooth and four-tooth and alternate four-tooth standards for age estimation of 1200 Indian children aged 5-15 years old.

Design: The study was designed as a retrospective cross-sectional study.

Results: Demirjian's original seven-tooth method overestimated age by 0.64 ± 1.44, 0.75 ± 1.50 and 0.69 ± 1.46 years in boys, girls and the total sample, respectively. Demirjian's revised seven-tooth method overestimated age by + 0.24 ± 0.80, + 0.11 ± 0.81 and + 0.19 ± 0.80 years in boys, girls and the total sample, respectively. Demirjian's original four-tooth method overestimated age by 0.79 ± 1.59, 0.59 ± 2.77 and 0.72 ± 2.30 years in boys, girls and the total sample, respectively. Demirjian's alternate four-tooth method overestimated age by 1.31 ± 1.07, 1.20 ± 1.10 and 1.26 ± 1.08 years in boys, girls and the total sample, respectively. Statistically significant differences were observed between dental and chronological ages with all methods (p <0.001).  Significant gender-based differences were observed only with Demirjian's revised seven-tooth and original four-tooth methods (p <0.05).  Conclusion: The revised seven-tooth standards most accurately predicted the age of the study sample (mean prediction error = 2.28 months), followed by the original seven-tooth, four-tooth and alternate four-tooth standards. The Demirjian original seven-tooth method was significantly more accurate in boys compared to girls, while the reverse was true for the Demirjian revised seven-tooth and original four-tooth methods.