Endo Resident Medical University of South Carolina Charleston, South Carolina, United States
The bevel for root-end resection at 90-degree is advocated to minimize the number of exposed dentinal tubules on the resected surface. However, literature demonstrates that dentinal tubules in apical area become more sclerotic with ageing. Thus, the exposed tubules on a beveled surface might not be permeable. Previous studies of the impact of bevel angle haven’t accounted for age.
Objective: The purpose of this study was to evaluate whether tubular permeability would be impacted by age and the bevel angle of resection.
Methods: Extracted single canal teeth were collected from age <30 (N=10) and age> 60 (N=10). Teeth were cleaned and shaped to F4, 1 mm short of apical foramen with a ProTaper Gold system. Smear layer was removed with 5.25% NaOCl and 17% EDTA. After coating with two layers of nail polish, samples were submerged in methylene blue dye overnight under a vacuum. A Buehler saw was used to section at a 30-degree bevel, followed by a 90-degree bevel, bucco-lingually along the long axis at 3 mm from the apex. The images of the resected surface at both bevels were captured using a Digital Optical Microscope. The maximal dye penetration in four directions and surface area were measured. The bevel angle effect and age effect were examined respectively with a paired t-test and an independent t-test.
Results: Our preliminary analysis showed no significant differences between bevels in both age groups. Neither patient age nor the bevel angle of resection affected the dye penetration in length or area.
