ACCURACY OF DEMIRJIAN AND WILLEMS METHODS FOR THE ESTIMATION OF THE CHRONOLOGICAL AGE

Keywords: dental age, Demirjian method; Willems method; x-ray images        
Dental development is widely used to estimate the chronological age. One method is that of Demirjian, applied in Franco-Canadian children, and that of Willems, adapted from the first one to Belgian children. The purpose of this study was to determine the accuracy of the methods of Demirjian and Willems in determining the chronological age through the calcification level of the tooth, in a population of San Miguel de Tucumán. 33 children for radiological studies prior to the general dental treatment, 16 female and 17male, in a range of ages between 4 and 12 were randomly selected. Each panoramic X-ray was taken and the images digitized with a scanner (Genius) with 600 dpi resolution. The dental age according to the method of Demirjian, which uses scores according to the calcification degree of the seven mandibular permanent teeth of the left side, was calculated through tables from those images. Willems method directly adapts the scale of scores of Demirjian method in years. Both methods are applied for both boys and girls. Chronological age was obtained between the date of birth and the date of the study. The chronological age in relation to the dental age data obtained with the methods of Demirjian and of Willems, was analyzed by the pairing T test with the statistical SPSS. Results for boys: there was no significant difference (p>0.05) between the chronological age and the estimated age with both methods. Demirjian overestimating the chronological age (x = 0.14±1,66); with Willems it is underestimated (x = -0.02±1,60). Results for girls: there was no significant difference (p>0.05) between the chronological age and the estimated age with both methods, which overestimated the chronological age; Demirjian (x=0.30±1,11), Willems (x=0.04±1,59). According to the obtained results in the selected sample, both methods for estimating the chronological age from the tooth calcification observed in x-ray images can be used. However, among them, the more accurate method was that of Willems either for both boys and girls.