The purpose of this study was to compare the efficacy of reciprocating and rotary techniques for removing gutta-percha and sealer from root canals. Forty straight and oval single-rooted premolars were prepared up to size 30, filled with gutta-percha and sealer, and then randomly allocated to two experimental retreatment groups: ProTaper Retreatment System (PTRS) and WaveOne System (WS). Procedural errors, time of retreatment and apically extruded material were recorded for all the roots. The roots were radiographed after retreatment. The percentage of residual material was calculated using image analysis software. The data were analyzed by Kolmogorov-Smirnov and t tests, with a significance level set at 5%. No system completely removed the root filling material from the root canal. No significant differences were observed between the systems, in terms of residual filling material in any tested third (p > 0.05). WS was faster in removing filling material than PTRS (p < 0.05). Extrusion was observed in 4 cases in PTRS and in 5 cases in WS. No procedural errors were observed in either group. It can be concluded that although no differences were observed in the efficacy of PTRS and WS for removing root filling material, WS was faster than PTRS.

Objective:The aim of this study was to evaluate the periodontal status of teeth indicated for undergoing endodontic treatment.Materials and Methods:Two hundred and nine teeth were evaluated using probing depth tests at three vestibular and three palatine/lingual sites before the patients underwent treatment. Teeth that presented up to 3-mm probing depth were considered as healthy. Those that presented at least one site with probing depth >3 mm were considered periodontally compromised. The data were statistically analyzed by means of applying the Chi-square test, with a level of significance of 5%.Results:Of the total of 209 teeth evaluated, 40 (19.10%) presented periodontal compromise. There was statistically significant difference related to the compromised teeth of patients of the female gender (22.80%) compared with teeth of patients of the male gender (12.30%) (P < 0.05).Conclusions:Fewer than 20% of the teeth evaluated presented a periodontal compromise. Patients of the female gender presented a higher number of periodontally compromised teeth than patients of the male gender.

Background: The effectiveness of endodontic retreatment essentially depends on the cleaning and/or disinfection processes. In this context, the removal of root canal filling materials plays a crucial role. Aims: To assess the efficacy of passive ultrasonic irrigation (PUI), EndoActivator system (EAS), and XP-endo Finisher R (XPEFR) as additional cleaning techniques to remove the remaining root canal filling materials from flattened root canals. Subjects and Methods: Thirty-six similar flattened distal root canals of extracted human first lower molars were selected by micro-computed tomography (micro-CT) and then instrumented and filled. After the initial retreatment procedures, the residual volume of root canal filling materials was assessed by micro-CT (V1). Then, the specimens were divided into three groups (n. 12), according to the additional cleaning technique and submitted to another micro-CT scan (V2). Statistical Analysis Used: Analysis of variance and Games-Howell tests ( P < 0.05). Results: The percentage reduction in the residual volume of root canal filling materials reached by PUI, EAS, and XPEFR was 28.38%, 28.12%, and 43.52%, respectively, considering the total space of the root canal ( P > 0.05). In the apical third, these values were 20.05%, 21.54%, and 48.82% ( P < 0.05). Conclusions: Additional cleaning techniques enabled removing a greater amount of root canal filling material from flattened distal root canals of extracted human first lower molars. Considering the total space of the root canal, there were no statistically relevant differences among the groups. In the apical third, XPEFR performed better.

Background: Due to the anatomical complexity of the root canal system, irrigation plays an essential role in endodontics. This in vitro study was sought to compare the removal of the smear layer (RSL) promoted by conventional irrigation (CI), passive ultrasonic irrigation (PUI) and continuous ultrasonic irrigation (CUI) with 17% EDTA, by using scanning electron microscopy (SEM). Material and Methods: Forty single-rooted human mandibular canines were instrumented and randomly assigned to four groups (n=10), according to the irrigation protocol aiming to the RSL: CG (control group) —conventional irrigation with distilled water; CI— conventional irrigation with 17% EDTA; PUI —passive ultrasonic irrigation with 17% EDTA; CUI— continuous ultrasonic irrigation with 17% EDTA. Hemisections from each sample were obtained, and images of each root canal third (cervical, middle and apical) were captured at 1000 X magnification by SEM. Three previously calibrated and blinded evaluators classified the RSL, according to the criteria proposed by Torabinejad et al.: small or no smear layer (all dentinal tubules were clean and open); 2 = moderate smear layer (no smear layer on the surface of root canal, but dentinal tubules contained debris); 3 = dense smear layer (covering practically all dentinal tubules entrances). Statistical analysis was performed by Kruskal-Wallis and Bonferroni tests (p<0.05). Results: Overall, CUI and cervical thirds showed better RSL rates, compared with the other methods and thirds, respectively (p<0.05). More specifically, the cervical thirds showed better results in the CG, CI and PUI groups (p<0.05), whereas the cervical and middle thirds were not significantly different in the CUI group. Conclusion: CUI was the most effective method for the RSL.