Age-related Variations at the Cementodentinal Junction: An Ex Vivo Study

The objective of this study was to determine the age-related anatomical changes that take place at the cementodentinal junction (CDJ).

Eighty-four teeth were extracted; 42 samples came from patients ranging in age from 18 to 30 years, and 42 came from patients aged from 40 to 60 years. Upper and lower and anterior and posterior teeth were included. Longitudinal slices were made, and 1% toluidine blue was used to stain all the samples prior to microscopic examination. Anatomical landmarks (apical foramen [AF], apical vertex, and cementoenamel junction) in the apical third were identified, and a pre-calibrated software package was employed to take digital measurements. Statistical analysis was performed by means of the Wilcoxon rank-sum test.

The data obtained showed that there were anatomical variations in the apical third in the older patients and that these changes were related to the age of the patient. Narrower root canals and smaller CDJ diameters were found in older patients' samples.

The results of this study suggest that instrumentation and obturation should take place 1 mm from the AF in older patients, and not 0.5 mm, as is usually recommended.