Apical enlargement: influence on the sealing ability of the vertical compaction technique.

This study sought to evaluate the influence of apical enlargement on the sealing ability of vertical compaction. Sixty anterior teeth were used. Half of these teeth were prepared to a size 25 file and the other half to a size 40 file. Then vertical compaction was performed. Apical microleakage was determined using pressurized fluid filtration at 90 min, 6 h, 1 day, 4 days, and at 1, 2, 4, 8, 12, 16, and 24 wk after root canal obturation. Leakage tended to increase over time for both groups. The size 25 file group showed significantly less apical leakage than the size 40 file group.