location of the apical foramen and its relationship with foraminal file size

Aim: This article analyzed the location of the apical foramen and its relationship with foraminal file size in maxillary central incisors. Methods: Eighty four human maxillary central incisors were used in this study. K-files of progressively increasing diameters were inserted into the root canal until it got snugly fit and the tip was visible at the apical foramen. The files were removed and teeth were crosssectioned 10 mm from the root apex. The files were then reinserted, fixed with a cyanoacrylate-based adhesive, and sectioned at the same level as the root. The root apices were examined using a scanning electron microscope set at 140x magnification, the images were captured digitally and the results were subjected to Chi-square test. Results: It was observed that 63 (75%) of the apical foramen emerged laterally to the root apex and 21 (25%) coincided with the apex. The results presented statistically significant differences (ג=22.1; p=0.00). Conclusions: Lateral emergence of the apical foramen is more common than coincidence of the foramen with the apex in maxillary central incisors. This anatomical characteristic may have influence on determination of the foraminal file size.