Frequency and Performance Analysis of Polymer, Steel, and Titanium Ultrasonic Inserts in Intracanal Medication...

Ultrasonic inserts can be manufactured in various shapes, angles, and materials, this study evaluated the frequencies generated by steel, titanium, and polymer ultrasonic inserts using acoustic wave analysis and assessed the effectiveness of the iVac system and passive ultrasonic irrigation (PUI) compared to conventional irrigation for removing calcium hydroxide-based intracanal medication using micro-computed tomography (microCT).

Steel and titanium inserts from the Ultra X system (blue, silver, gold) and the polymer insert from the iVac system were analyzed using vibroacoustography in Ultra X (45 kHz) and Woodpecker (40 kHz) ultrasonic devices. Inserts were positioned in a water tank for standardized placement. The excitation signal was generated using MATLAB software, and power measurements were conducted in duplicate. After root canal preparation in 30 teeth, calcium hydroxide-based medication was applied and scanned using microCT. After 7 days, initial removal was performed with a K-file (number 45.02), followed by three protocols: conventional irrigation, PUI, or iVac. A second microCT scan was performed. Analysis of variance and Tukey's tests compared ultrasonic power and residual medication volume.

The steel, titanium, and polymer inserts exhibited frequencies from 37 to 45 kHz. The iVac group (99.8 ± 0.3%) achieved greater medication removal than the PUI group (97.3 ± 2.9%), both significantly superior to conventional irrigation (73.0 ± 9.4%) (P < .05).

The ultrasonic power of the inserts operated within the expected frequency range. The iVac system demonstrated superior effectiveness in removing intracanal medication.