Three-Step versus Single-Step Use of System B: Evaluation of Gutta-Percha Root Canal Fillings and Their Adaptation to the Canal Walls.

摘要

This study aimed to evaluate the quality of gutta-percha (GP) root canal fillings and their adaptation to the root canal walls, when the System B was used in three steps and a single step to fill three different split-tooth models. Each model was filled 10 times in two different ways. Group A: the System B plugger was used to fill the apical 3 mm of the canal in three steps, and then the Obtura II was used to backfill the rest of the canal. Group B: the System B plugger was inserted just once to a distance 3 mm short of the working length and then backfilled as in Group A. Replication of artificial depressions, presence of voids within the GP mass, and presence of spaces between the GP mass and the root canal walls were evaluated and scored. The individual scores of each parameter evaluated were compared between the two groups and statistically analyzed by use of the Mann-Whitney U test. Group A showed statistically significant (p < 0.05) better scores than Group B concerning the replication of artificial depressions and spaces between the GP mass and the canal walls. It was concluded that better adaptation of the GP mass to the canal walls in the apical third was obtained when the System B plugger was used in three steps.