Forensic age estimation in living or dead individuals is an important and difficult task. Teeth are considered a reliable indicator of age and provide a number of parameters for age prediction. The aim of this study was to estimate the age in a sample of Egyptian population using the tooth coronal index (TCI) in the mandibular permanent 1st molars in dental panoramic radiographs. Digital panoramic radiographs from 170 participants of known age and sex were included. They were used to measure the crown height (CH) and the coronal pulp cavity height (CPCH) in millimeters. Then, TCI was calculated according to Ikeda et al., (1985). Non significant statistical difference was observed between females and males as regards the TCI. A significant negative linear correlation between chronological age and values of TCI was detected. The correlation coefficients were -0.988, -0.987 and -0.986 in all participants, female participants and male participants respectively. The values of TCI were then subjected to regression analysis to derive equations for age estimation. Regression equations showed coefficient of determination (R2) of 0.984, 0.986 and 0.982 in all participants, female participants and male participants respectively. It was concluded that calculation of the TCI from the mandibular permanent 1st molars is a good predictor of age among Egyptians. Regression equations based on TCI were established and they proved to be very useful for prediction of age with no need for sex specific equations. So, calculation of the TCI is recommended as an easy method for age estimation. Further studies on larger sample size and studies using teeth other than the mandibular permanent 1st molars are needed.