Use of the Demirjian method to estimate dental age in panoramic radiographs of patients treated at the Buenos Aires University School of Dentistry

Abstract

The aim of this study was to determine the difference between real age (RA) and dental age (DA) in boys and girls from the Autonomous City of Buenos Aires (C.A.B.A.) by analyzing digital panoramic radiographs from the database of the Imaging Department at the Buenos Aires University School of Dentistry, using the Demirjian Method (DM). The sample consisted of 508 panoramic radiographs of 6- to 14-year old Argentines (268 female and 240 male). The Demirjian method was used to estimate dental age from each panoramic radiograph, and the Wilcoxon test was applied to perform a comparative analysis with the real age recorded in the image database. Average RA was 9.36 years (SD 2.11), and average DA according to the Demirjian method was 10.45 years (SD 2.31). For females, RA was 9.25 (SD 2.12), and DA according to the DM was 10.40 years (SD 2.41). For males, RA was 9.46 (SD 2.10), and DA according to the DM was 10.50 years (SD 2.22). An inter-class correlation coefficient (ICC) calculated as a correlation measure between dental age and real age was ICC = 1.09%. The ICC was 1.04% for the males and 1.15% for females. Significant differences were found between DA and RA (p <0.01) in general and according to sex. Real age was found to be lower than dental age in the study population from Buenos Aires City.

Adapting Demirjian Standards for Portuguese and Spanish Children and Adolescents

“…The application of the London atlas of tooth development and eruption showed an average overestimation of age by only one month in the Portuguese population, although further studies are needed [51]. Applying the Demirjian method to samples of different nationalities has largely led to authors concluding on overestimation of dental age, although some studies have indicated underestimation [31,35,52]. Among the studies finding underestimation is that of Cruz-Ladeira et al [53] with Venezuelan subjects and that of Chen et al [54] with Chinese individuals, although underestimation only occurred in boys; this result agrees with the 11 to 12 age group in boys in this study, where the method pointed towards slight underestimation.…”

“…Simple and multiple linear regressions were used to obtain a parsimonious model, allowing estimation of chronological age from the measurements made of the seven teeth based on each method and the variables of sex and age group, since in previous studies the Demirjian method is shown to be sensitive to these variables [7,30,[35][36][37][38]. Using regression equations provides a more precise approach to chronological age based on Demirjian's staging method [43].…”

“…The literature review tends to show that estimating chronological age by means of the dental mineralization stage is not a straightforward analysis as some contingent factors may influence the relationship, namely age group, sex, and the tooth under analysis. Several researchers found that the Demirjian standards need re-specification in order to correct for the over-estimation (e.g., Stamm et al [35] for the population from Buenos Aires City; Moca et al [36] for Romanian children). Staaf et al [37] and Sobieska et al [30] also found an overestimation of the Demirjian standards, the same occurring with a sample of Chinese children [38].…”