Radiographic evaluation of third molar development as an indicator of chronological age by demirjian and kohlers methods

Aim: To determine the developmental stages of third molars on digital orthopantomogram in relation to the chronological age of an individual in Indian population and to compare the accuracy of two different methods [Demirjian and Gleiser and Hunt modified by Kohler]. Materials and Methods: The study consist of 100 subjects (50 males, 50 females) attending Vydehi Institute of Dental sciences and research center. The panaromic radiograph of each subject was taken. The image of panaromic radiograph taken was imported into Adobe Photoshop CS2 (Adobe Systems Incorporated, San Jose CA) to enhance the view. Development of third molar was evaluated according to the scoring method of Demirijian et al. & Gleiser and Hunt modified by Köhler et al by two observers. Repeated scoring was done by both the observers with time interval of 2 months. Results: It was found that intra and inter observer agreement was better for the method given by Demirjian et al than Kohler’s method though both the method showed moderate agreement. Conclusion: Mean mineralisation age of third molar was earlier in males than females according to staging criteria given by both the methods. It was also found that coefficient of determination (R2) in males was relatively high for Demirjian’s method than that of the Kohler’s method where as it was same for females according to both the methods.