In-vitro study comparing the self-adjusting file to the Vortex RTM rotary file with passive ultrasonic irrigation on the seal of root canal fillings in oval shaped canals

The purpose of this microleakage study was to use the glucose penetration model to compare the cleaning and shaping efficacy of the self-adjusting file system (SAF) to the Vortex® rotary file augmented with passive ultrasonic irrigation (PUI) in long, oval shaped canals. A total of 44 single rooted, straight canals of extracted human teeth were used in this study with 22 samples in each of the two groups. All samples were subject to their respective instrumentation protocol and obturated with a continuous wave technique using AH plus® sealer. Using the glucose penetration model, a 1.5 kPa of hydrostatic pressure pushed 1 mol/L of glucose solution down the root. Duplicate 12 µL aliquots were collected from the reservoir of each sample on days 1, 2, 7, 14, and 28. In each sample, the level of glucose was determined based on the glucose-oxidase reaction using the QuantiChrom™ Glucose Assay Kit. The concentration of glucose was determined spectrophotometrically at 630nm. Results showed that the SAF leaked significantly more in days 1, 2, 7, and 14 than the Vortex ® with PUI. The overall statistical significance was calculated using the ANOVA test, yielding a p-value of 0.0064. In conclusion, the SAF did not result in improved sealing outcomes when compared to the Vortex ® rotary file used in conjunction with PUI. According to the results of this study, the SAF did not offer an improved method to cleaning and shaping long, oval shaped canals.