Development stages of third-molar tooth for estimation of chronological age in children and young adult

Aim: To evaluate judgment of chronologic age based on the stages of third-molar growth following the eight stages (A-H) technique of Demirjian et al and to compare third-molar development by age and sex with outcome of previous studies. Methods: The study was conducted in Dental Unit D.H.Q, Teaching Hospital affiliated with Gomal Medical College, D.I.Khan. The final sample consisted of 300 orthopantomograms from young Pakistani population of known chronologic age (range, 9-26 years; mean age, 15.94±3.72 years) and sex (130 males with a mean age of 15.53±3.75; 170 females with a mean age of 16.36±3.89). The Mann-Whitney U-test and the Wilcoxon test were applied for statistical analysis between sex and age. Regression analysis was performed to obtain regression formulas for dental age calculation with the chronologic age Results: In third-molar growth between males and females were showed about the calcification stages D and G (P<0.05, statistically significant differences). The genesis of third-molar was attained earlier in males than in females. A strong correlation was showed between age and third-molar growth for males (r²=0.64) and for females (r²=0.60). Equations (Age=9.42±1.60 Development stage) were derived for chronologic age estimation. Conclusion: The third-molars is a appropriate developmental marker, particularly when comparing the obtained standard deviation with other skeletal age calculation methods.