This research aims to compare the in vitro apical microleakage between lateral condensation and System TM BeeFill 2 in 1. Chemomechanical were prepared with 5.25% sodium hypochlorite and EDTA to remove the smear layer, single-rooted premolars of 50 straight pipes and unique and were randomized into four groups: two experimental groups of 20 pieces each, sealed with the lateral condensation technique BeeFill system TM 2 in 1, a positive control group and a negative control group of five pieces each, not sealed. All parts were dried five days and then placed a layer of enamel on the root surface except the apical 4 millimeters. The negative control group as a whole is varnished. They were then immersed in test tubes with black India ink neutral pH and placed in the centrifuge for 5 minutes at 3000 rpm and passive immersion for three days at 37 oC. Were washed by removing the remains of nai...