Influence of Passive Ultrasonic Irrigation on the Removal of Root Canal Filling Material in Straight Root Canals

Abstract

Objective: This study evaluates the efficacy of passive ultrasonic irrigation (PUI) in removing root canal filling material from endodontically treated teeth after using one of two reciprocating systems, Reciproc (VDW, Munich, Germany) or WaveOne (Dentsply Maillefer, Ballaigues, Switzerland), or one nickel-titanium (NiTi) rotary system, ProTaper Universal Retreatment (Dentsply Maillefer). Methods: One hundred and twenty straight root canals of extracted human maxillary incisors were instrumented and then obturated. The specimens were divided into six groups (n=20) as follows: Group R, Reciproc R25 instrument without PUI; Group W, WaveOne Primary instrument without PUI; Group PT, ProTaper Universal Retreatment system without PUI; Group R-PUI, Reciproc R25 with PUI; Group W-PUI, WaveOne Primary with PUI and Group PT-PUI, ProTaper Universal Retreatment system with PUI. After removing the filling material, the teeth were cleaved longitudinally and photographed. The total canal space and remaining material were quantified with the aid of an imaging software tool. The Kruskal-Wallis test was used to identify significant differences between the groups. Results: No statistically significant differences (P>0.05) in residual filling material were observed between the groups. Conclusion: The use of PUI did not improve the removal of filling material from the root canals, regardless of the previously used instrumentation system.

Modern supplementary strategies of filling material removal in non-surgical root canal retreatment

“…Passive ultrasonic irrigation (PUI) is one of the most studied approaches for activating irrigating solutions in the literature and is based on a passive ultrasonic tip vibrating at ultrasonic frequency inside the root canal with an irrigation solution. Despite controversial results, most studies indicate better performances in the addition of this resource for removing filling materials remnants after initial bulk removal with NiTi preparation systems (Bueno et al, 2017;Gomes et al, 2017;Castro et al, 2018;Silveira et al, 2018;Crozeta et al, 2020). The influence of PUI on the outcome of secondary treatment is still unknown, the only study published on the subject to date is a retrospective clinical study that found higher survival rates in retreatments associated with PUI (Bartols et al, 2020).…”

Critical analysis of research methods and experimental models to study removal of root filling materials

“…Early studies used hand instrumentation techniques, such as the Step-Back and Crown-Down, to prepare the tooth samples (Barletta et al, 2007;de Oliveira et al, 2006). With the introduction of engine-driven nickel-titanium instruments, the tooth samples are now usually prepared using one of these systems (Bueno et al, 2017;Campello et al, 2019;Uzunoglu et al, 2015).…”