Comparison of the sealing efficacies of two obturation techniques in curved root canals instrumented with and without ultrasonic irrigation.

Volumetric dye penetration into the canals of 131 teeth was studied spectrophotometrically. The teeth were first divided into three groups according to the degree of curvature. Each group was then subdivided into four groups, in which the Thermafil and lateral condensation techniques were used with or without ultrasonic irrigation. Significant microleakage differences were observed between group I (0-10 degrees) and group III (21-30 degrees) for lateral condensation filling with ultrasound irrigation and Thermafil filling without ultrasound irrigation (p < 0.05).