Purpose: to determine the effect of different angles of apical resection and depths of retrograde filling on apical leakage.
N= 27 extracted teeth
•The crowns were removed and the roots were divided into 3 groups of 9 corresponding to the angle of root resection (0, 30,45), the resection was commencing 2 mm lingulally from the apex for 0 group and 1 mm for 30 and 45 groups.
•Retrograde filling (ketac Silver) was placed as increments in the resected roots
•leakage was measured using a hydraulic conductance apparatus after placing of each filling increment in each of the 3 groups.
•Any roots exhibiting leakage through accessory canals were excluded from the study.
Most highlighted Results:
dye leakage could be seen at the apex of the
•There was a significant increase in apical leakage as the amount of the bevel increased. Statistical differences in leakage were found between the 0-degree group and both the 30° (p < 0.002) and the 45° (p < 0.0001) groups, but not between the 45 and 30° groups (p < 0.1002).
•increasing the depth of the retrograde filling significantly decreased apical leakage (p < 0.0001)
To reduce leakage, the angle of the beveled root face should be kept to a minimum, when the bevel increased, the depth of the retrograde filling should be increased.