Continuous Wave of Condensation Improves the Filling of Curved Canals: a Micro-CT Study

Abstract

The aim of this study was to compare the filling capacity in curved root canal using a new continuous wave of condensation technique (Termo Pack II, Easy Dental Equipments, Brazil) or lateral compaction. The percentage of voids in the filling of mesial root canals of mandibular molars was assessed by micro-computed tomography (micro-CT). Mesial root canals (n=24) of mandibular molars with a degree of curvature between 20° and 40° were prepared using rotary system (ProDesign Logic, Easy, Brazil) up to #35, .05 taper. The root canals were filled by using the continuous wave of condensation system or lateral compaction and AH Plus sealer (n=12). Scanning at 9 µm was performed after preparation and after filling by using micro-CT SkyScan 1176. The volumetric percentage of filling material and voids (total length and in each root canal third) were calculated. Data were analyzed using ANOVA/Tukey and Student’s t tests (α=0.05). Before the filling techniques, the root canals volume after preparation was similar (p>0.05). The root canals filled by the continuous wave of condensation technique presented the lowest percentage of voids, and the greatest percentage of filling material in total length and thirds (cervical, middle and apical) (p<0.05). Both techniques were not able of completely filling the root canals. The continuous wave of condensation technique Termo Pack II promoted better root canal filling in curved root canals, when compared with lateral compaction.

A Scanning Electron Microscopy Study Comparing 3 Obturation Techniques to Seal Dentin to Root Canal Bioceramic Sealer in 30 Freshly Extracted Mandibular Second Premolars

“…The larger gap voids in the apical third for the CWT obturation may be attributed to the technique used, since the heated tip is not meant to reach the apical third. When compared to other groups, the CWT had smaller marginal gaps in the apical third, which agrees with earlier studies [23,37]. Our results for CWT marginal gap width comparison among apical, middle, and coronal thirds are contrary to those obtained by Pinto et al [37], who reported low void percentage in the apical third when compared to the coronal and middle thirds.…”

“…When compared to other groups, the CWT had smaller marginal gaps in the apical third, which agrees with earlier studies [23,37]. Our results for CWT marginal gap width comparison among apical, middle, and coronal thirds are contrary to those obtained by Pinto et al [37], who reported low void percentage in the apical third when compared to the coronal and middle thirds. Among the 3 techniques, the CWT also showed less voids in the coronal third, which agrees with previous studies [38,41].…”

“…Different techniques of CLCT (manual, mechanical, and ultrasonic) have been investigated but were found to cause void areas within the canal [36]. These voids have been attributed to the use of a spreader that generates larger spaces than with other cones [37]. The superiority of CWT obturation in terms of better marginal adaptation and concomitantly smaller gap voids have been attributed to its ability to allow plasticization of the entire length of gutta-percha cone., which creates a mass that is homogenous and can fill minor irregularities [38].…”