Background: Coronal leakage is a significant cause of failure in endodontically treated teeth. This study aimed to evaluate the effect of fiber post-exposure on coronal microleakage in endodontically treated teeth that were restored with fiber post and composite core.
Method: Forty-Five extracted maxillary incisors were endodontically treated and randomly divided into five groups. The specimens in the first group were restored with fiber post and core while the post wasn't exposed and covered with composite. The fiber posts were exposed in the second and fourth groups, while fiber posts and luting cement were exposed in the third and fifth groups. The first, second, and third groups were varnished, up to one millimeter below CEJ, and the fourth and fifth groups up to the highest level of composite core. After 5000 thermal cycles, specimens were immersed in 2% Methylene blue for 72 Hours, cut into two halves longitudinally. Microleakage was examined with dye penetration using a stereo microscope. Mann- Whitney U-test and Kruskal Wallis test were performed to determine significant differences among the microleakage of each group.
Result: No difference was observed in microleakage values between groups at the incisal interface (fiber post-cement-composite), also the groups with nail varnish under the CEJ, showed no significant difference in microleakage at the cervical interface, which was not affected by fiber post-exposure at incisal region.
Conclusion: There was no significant difference in microleakage values among groups with exposed and non-exposed fiber posts at the fiber post-cement-composite interface.