Disinfection of the root canal system is a major goal of endodontic treatment, but is challenging because residual dental pulp tissue, bacteria, and dentine debris can remain in parts of the root canal system that are left uninstrumented after root canal preparation.
To improve disinfection of the root canal system, a number of antimicrobial and tissue-dissolving irrigants are used routinely, which are applied using conventional syringes or more specialized devices. While conventional needle irrigation is used widely, its ability to deliver a vigorous flushing action in the confines of the root canal space is limited, and as a result debris often remains in root canal irregularities.
Today, a number of approaches are recommended for enhancing the flushing action of irrigants, such as sonic and ultrasonic agitation, in an attempt to achieve better removal of smear layer, debris and bacteria. A recent major development is the Vibringe System (from Vibringe B. V. Corp, Amsterdam, The Netherlands), which combines manual delivery and sonic activation of the solution. The system comprises a cordless handpiece that fits in a special disposable 10 mL Luer-Lock syringe that is compatible with all current irrigation needles.
A recent study from the University of Gottingen, Germany, published in the Journal of Endodontics in August 2010* compared the efficiency of conventional syringe irrigation with the Vibringe System and with passive ultrasonic irrigation (PUI) in terms of the removal of dentine debris from simulated root canal irregularities in maxillary lateral incisor teeth on the bench. Root canals were prepared with 2 standardized grooves in the apical and coronal thirds and were then filled with a sand-like mixture of dentine chips and sodium hypochlorite, to simulate the clinical situation when dentine debris accumulates in uninstrumented root canal extensions. The canals were then irrigated with 1% sodium hypochlorite solution using a conventional syringe irrigation through a 30 gauge needle, the Vibringe system with the same needle and same solution, or by passive ultrasonic irrigation using a Piezon Master 400 scaler set at one quarter power for agitating a size 15 K file. After irrigation, digital photographs of the canal walls were taken, which were then scored at 30X magnification for remaining debris using a 4-grade scoring system.
The Vibringe System demonstrated significantly better results than conventional syringe irrigation in the apical part of the root canal, but was not as effective as ultrasonic irrigation. In the groove in the coronal region, the difference between syringe irrigation and the use of the Vibringe System was not statistically significant. Debris was completely removed after irrigation with the Vibringe System in 5% of the specimens, and after passive ultrasonic agitation in 92.5% of the specimens. The more effective removal of debris with ultrasonic irrigation compared with sonic activation has been demonstrated in other studies, and this difference in performance is likely due to the higher power as well as higher driving frequency of ultrasound (30 kHz) than the Vibringe sonic device (150 Hz), meaning a lower irrigant flow velocity and thus lower cleaning efficiency.
A key point from the study is that the Vibringe System performed better than conventional syringe irrigation in the apical third, which is probably due to a higher oscillation amplitude of the sonically activated irrigation needle at the tip than at the attached end, resulting in an increased fluid velocity.
Rodig T, Bozkurt M, Konietschke F, Hulsmann M. Comparison of the Vibringe System With Syringe and Passive Ultrasonic Irrigation in Removing Debris From Simulated Root Canal Irregularities. Journal of Endodontics 2010; 36(8):1410-1413.