Evaluation of two shaping systems and two sonic irrigation devices in removing root canal filling material from distal roots of mandibular molars assessed by micro CT

Abstract

Aim To compare two preparation systems and two sonic irrigation devices during the removal of root filling material from oval distal canals of extracted mandibular molars. Methodology The distal canals in 40 extracted mandibular molars were shaped using the ProTaper Next system (Dentslpy Sirona, Ballaigues, Switzerland), filled with Gutta Percha X2 (Dentsply Sirona), along with AH Plus sealer (Dentsply De Trey, Konstanz, Germany) and randomly divided into two groups (n = 20) according to volume of initial filling, preparation diameter and working length. One group was retreated using the Reciproc system (VDW, Munich, Germany), and the other using the 2Shape system (Micro‐Mega, Besançon, France). A micro‐CT scan was taken after the initial root filling and after retreatment to evaluate the volume of filling material remnants. The teeth were divided into four groups to test the supplementary effect of two sonic irrigation devices on removing filling material: Eddy (VDW) and MM1500 (Micro‐Mega). In the first and second groups, 2Shape was followed subsequently by MM1500 and Eddy; in the third and fourth groups, Reciproc was followed by MM1500 and Eddy. A third micro‐CT was taken to compare the remaining root filling material in all groups. Wilcoxon's signed rank tests, Mann–Whitney and Kruskal–Wallis tests were used for statistical analysis. Results No significant difference was found for the volume of filling material removed between the Reciproc and 2Shape in the entire canal (P = 0.355). The volume dropped significantly from its initial value after removing the bulk of the root filling by 95.8% (from 4.71 to 0.22 mm3) with the 2Shape (P < 0.001) and by 94.0% (from 5.05 to 0.33 mm3) with the Reciproc (P < 0.001). Sonic activation significantly decreased the residual volume of filling material remnants by 3.21% (P = 0.013) in the first group, 1.38% (P = 0.012) in the second group, 1.83% (P = 0.008) in the third group and 1.83% (P = 0.012) in the fourth group. At the end, the percentage of residual material was not significantly different among the groups in the entire canal (P = 0.163). Conclusion In the distal oval canals of extracted mandibular molar teeth, there was no significant difference between the 2Shape and Reciproc systems in removing gutta‐percha/sealer. Sonic activation with MM1500 and Eddy significantly improved filling material removal.

Sonic irrigant activation for root canal disinfection: power modes matter!

“…Recent in vitro studies have shown that, compared with manual irrigation, the sonic irrigation device EDDY improves the dentin debris removal from artificial canal irregularities [14], the removal of calcium hydroxide from artificial grooves in the root canal of maxillary incisors [9], the removal of remnants of sealer and guttapercha [15] and the median dye penetration depths in dentinal tubules of apical root sections [16]. However, considering the pivotal etiopathogenetic role of endodontic biofilms in periapical disease, the reduction of the microbial load within root canal systems is arguably the most relevant surrogate marker in experimental irrigation studies [17].…”

Analysis of the quality of root canal preparation and retreatment using different instruments associated or not with different irrigant agitation protocols

“…The Eddy instrument presented a significant reduction in the amount of remaining filling material, corroborating with the results found by Kaloustian et al (2019a). The effectiveness of this instrument is related, according to the manufacturers, to the formation of cavitation and acoustic streaming within the irrigant produced by the high frequency (6000 Hz) to which the polymer tip (Eddy) is used (Kaloustian et al 2019a).…”

“…Eddy (VDW, Munich, Germany) is a polymer tip that is activated by sonic vibrations by a conventional air scaler operating at a frequency of 6000 Hz . Studies have shown encouraging results where Eddy has been shown to be effective in biofilm and smear layer removal, and has improved the dissolution of organic tissue and removal of filling material during retreatment (Conde et al 2017, Urban et al 2017, Kaloustian et al 2019a, Swimberghe et al 2019.…”

Die mechanische Aktivierung von Wurzelkanal-Spüllösungen – eine Literaturübersicht

“…Auch bei der Entfernung von Kalziumhydroxid, das als medikamentöse Einlage verwendet wurde, erwies sich der EDDY als der manuellen Spülung überlegen und der PUI vergleichbar [12]. Im Zuge von Revisionstherapien fördert der EDDY die Entfernung von Füllmaterial nach der mechanischen Entfernung mit Nickel-Titan-Instrumenten [22]. Im Modellversuch konnte ein Biofilm mit dem Endo-Activator ebenso wenig aufgelöst werden wie mit der manuellen Irrigation [11,23].…”