Evaluation and Comparison of the Accuracy of Nolla and Demirjian Methods for Age Estimation in a sample of Egyptian Children Using Panoramic Radiographs (A Retrospective Study)

Abstract Background Age estimation is an important procedure in forensic field. It is very crucial for the identification of both living and dead persons. For living it is performed in circumstances where the birth certificate is not available or the records are suspicious. This could be of value in civil conflicts e.g. marriage, employment, military recruitment, inheritance and adoption. Also it is important in criminal cases involving rape, kidnapping and illegal immigration, as well as for medical cases as pediatric endocrinopathy and orthodontic malocclusion. Age estimation of cadavers is performed in criminal cases, as well as for identification of mutilated victims of mass disasters, such as fires, crashes, accidents, feticides, homicides and infanticides. Aim Estimation the age of a sample of Egyptian children through using both Nolla and Demirjain methods, Comparison of these ages with their chronological ages and then assessing the accuracy of these methods in age estimation. Methods A retrospective study was performed on panoramic radiographs of 180 subjects aged less than 6–16 years. The mean dental age (DA) according to the Demirjian and Nolla methods were compared to the mean chronological age (CA). Results The mean CA of the study sample was 9.90±2.71 and 9.40±3.23 years for females and males, respectively. Using the Demirjian method, the mean estimated DA was 9.38±2.09 years for females and 9.77±3.01 years for males. For Nolla method, the mean estimated DA was 8.48±1.79 and 9.07±2.77 years for females and males, respectively. The mean differences between the CA and DA according to the Demirjian were -0.52 and 0.37 years for females and males, respectively. For Nolla method the mean differences were -1.42 and -0.33. Conclusions Nolla method was found to be a more accurate method for estimating DA in Egyptian population. The predictive ability of Nolla method by linear regression analysis was 98%.