Background : Age estimation is an important factor in forensic science for human identifcation. Teeth resist decomposition at death unlike other tissues. The gradual structural changes that take place throughout the life have made teeth useful indicators for age estimation.Cemental annulation is a microscopic method for the determination of age based on the analysis of incremental lines of cementum. Light microscopy as well as specialized microscopic techniques have been employed to enhance the assessment of the cemental annulations. Aim : To estimate age with cemental incremental lines in human teeth using phase contrast and stereomicroscope. Materials and methods : A total of 51 normal teeth were included in the study (sound teeth without any associated pathologies). Longitudinal ground sections were observed under phase contrast microscope and stereomicroscope. The number of incremental lines in the total cementum width was calculated with thefollowing formula: Number of incremental lines (n) = X/Y where X is the total width of cementum (from DCJ to cementum surface) and Y is the width of cementum between the two incremental lines. Estimated age (E) = number of incremental lines (n) + eruption age of tooth (t) Results : The measurements obtained were subjected to statistical analysis for age estimation. Statistically significant results were obtained with phase contrast microscope as compared to stereo microscope. Conclusion : Age estimation by cemental annulation using phase contrast microscope is a reliable method and can be easily applied in forensic odontology.