Age estimation in adult human sound and periodontally affected teeth using tooth cementum annulations

Background: There are many tools for identification of human remains, via radio graphical imaging, histological processing microscopical examination of dental remains. Purpose: to estimate the age of both female and male adults using tooth cementum annulations (TCA) method, evaluate the accuracy of TCA of both sound and periodontally affected teeth, and compare the estimated age (Est.age) with the chronological age (Chr.age) of an individual by the aid of; light microscope (LM), polarized microscope (PM) and phase contrast microscope (PHM). Material and methods: 60 teeth divided into four equal experimental groups; group I contained sound teeth extracted from female patients, group II contained sound teeth extracted from male patients, group III contained periodontally affected teeth extracted from female patients and group IV contained periodontally affected teeth extracted from male patients. Longitudinal ground section for all groups were prepared observed under LM, PM and PHM. Afterward, images were taken for each section then the average of TCA for each section was counted. The age was estimated using the formula {Estimated age = Numbers of incremental lines þ Eruption age of tooth}. Results: There was no significant difference between Est.age and Chr.age of both male and female sound teeth (group I and group II) while in periodontally affected teeth of both male and female (group III and group IV) there was significant difference. Also, there was a strong correlation between the Est. Chr. age when PHM was used followed by LM then PM. Finally, there was no sex difference. Conclusion: TCA is reliable for sound but not for periodontally affected teeth using either LM, PM or PHM. Moreover, PHM is a more accurate microscope for TCA in contrast to LM PM. Interestingly, a novel regression formula was developed to enable estimating age in periodontally affected teeth by TCA method.