The correlation between the reduction of the coronal pulp cavity and the chronological age was examined in a sample of 532 intact mandibular second premolar from 266 Individuals of known age and sex. A panoramic radiographic examination was conducted on the selected individuals. Panoramic radiography was used to measure the length (mm) of the tooth crown (CL=coronal length) and the length (mm) of the coronal pulp cavity (CPCL=coronal pulp cavity length). The tooth-coronal index (TCI) after Ikeda et al. (1985) was calibrated with the computer software for accuracy and precision for each tooth. The values obtained were then subjected to regression analysis to derive equations for age estimation. The results were calculated and correlated with the chronologic age for evaluation. The correlation coefficients between chronological age and tooth coronal index ranged from -0.963 to -0.925. Regression equations derived for age estimation utilizing TCI for Egyptian population showed coefficient of determination (r2) ranging from 0.843 to 0.862 .This study shows the potential value of tooth coronal index aging method, which can be easily used to estimate age.