The sealing ability of an epoxy resin root canal sealer used with five gutta-percha obturation techniques

The purpose of the present study was to evaluate the apical sealing ability of an epoxy resin root canal sealer (AH-26) when used with different gutta-percha obturation techniques (i.e. cold lateral condensation, warm vertical condensation, hybrid condensation) and with Thermafil and Soft-Core obturators. Straight single-rooted teeth with mature apices were prepared according to the crown-down/step-back technique and divided in five groups of 45 teeth and one group of 12 control teeth. After root canal filling 15 teeth of each group were kept for 1 day, another 15 teeth for 1 week, and another 15 teeth for 4 months at 37 degrees C in vacutainers in 80% relative humidity. The 237 teeth were immersed in india ink for 90 hours, each root was split and sectioned longitudinally, and the maximum extent of leakage was measured using a stereomicroscope at x6 magnification. It became clear that leakage occurred whatever technique was combined with AH26 and that leakage increased with time. The amount of apical leakage and the number of leaking teeth in the Soft-Core obturator groups was significantly higher than all other 4 gutta-percha obturation techniques combined with AH26. In this respect, the hybrid gutta-percha condensation technique turned out to be superior to the four other condensation techniques.