The mineralization of third molar is one of the main criteria for radiological dental age estimation of living subjects .The ethnic populations residing in different countries have been insufficiently analyzed therefore; this study was planned for dental age estimation on specific population. Few studies have been published on accuracy, validation and correlation of tooth staging of different methods and dental age estimation. Hence, it is important to find out the correlation between the tooth staging methods. A total of 800 orthopantomograms were collected from the original South Indian population of Haryana and New Delhi divided in age categories between 15 and 27 years. On the radiographs, the developmental stage of the third molar was scored, applying a nine scoring methods such as Gleiser and Hunt, Haavikko, Demirijian, Harris & Nortje, Moorrees et al, methods. Statistical analysis were obtained on data such as Multiple regression formulas ,Root mean squared errors for absolute error made in age prediction, R2 for correlation between age and different scoring methods, Spearman correlation coefficient for correlation contralateral third molars, probabilities to be older than 18 and 21 years is given a specific score for mandibular and/or maxillary and JK cross-validation for the expected error in the age prediction. The multiple regression models and mean absolute error were calculated. Comprising of different tooth staging methods revealed that, males are highly correlated with tooth staging as compared to females; Demirijian and Morrees et al Gleiser and Hunt methods have more statistical significant correlation than other tooth staging methods. No statistical significant difference between antimeres is found. The probability of being older than 18 years is high as compared to 21 years is established.

Key Words: Forensic odontology, Dental age estimation, Third molars, Orthopantomograms, Tooth Staging methods, South Indian population.