Effectiveness Of ProTaper Research Articles

Endodontic retreatment due to secondary periapical injury: case report

Endodontic retreatment due to secondary periapical injury: case report

Effect of ProTaper and Reciproc preparation and gutta-percha cone on cold lateral compaction.

Context:The effectiveness of cold lateral compaction depends on the root canal preparation and used gutta-percha cone.Aims:The aim of this study is to evaluate finger spreader penetration into root canals prepared with ProTaper (PT) or Reciproc (Rec) systems and filled with gutta-percha cones with different tapers.Materials and Methods:Twenty-four simulated root canals in resin blocks with 30° curvature were prepared up to PT F2 or Rec R25. They were divided into four experimental groups according to the master gutta-percha cone and preparation (25.02 or F2/PT, and 25.02 or R25/Rec). Cold lateral compaction was performed using a stainless steel finger spreader size B. The set cone-finger spreader-resin block was placed in a universal test machine, and a load up to 1.5 kg was applied on the finger spreader. The final distance between the finger spreader and apical preparation after load application was obtained. For comparison among the groups, data were submitted to ANOVA and Tukey's tests, with a significance level of 5%.Results:Greater finger spreader penetration was observed for 0.02/Rec and 0.02/PT, followed by F2/PT and R25/Rec.Conclusion:The use of cones associated with PT and Rec preparations does not allow the finger spreader penetration up to the apical third.

Micro–computed Tomographic Assessment on the Effect of ProTaper Next and Twisted File Adaptive Systems on Dentinal Cracks

IntroductionThe aim of the present study was to evaluate the frequency of dentinal microcracks observed after root canal preparation with ProTaper Next (PTN; Dentsply Maillefer, Ballaigues, Switzerland) and Twisted File Adaptive (TFA; SybronEndo, Orange, CA) systems through micro–computed tomographic analysis. MethodsTwenty moderately curved mesial roots of mandibular molars presenting a type II Vertucci canal configuration were randomly assigned to 2 experimental groups (n = 10) according to the system used for the root canal preparation: PTN or TFA systems. The specimens were scanned through high-resolution micro–computed tomographic imaging before and after root canal preparation. Afterward, pre- and postoperative cross-sectional images of the mesial roots (N = 25,820) were screened to identify the presence of dentinal defects. ResultsDentinal microcracks were observed in 38.72% (n = 5150) and 30.27% (n = 3790) of the cross-sectional images in the PTN and TFA groups, respectively. All dentinal defects identified in the postoperative scans were already present in the corresponding preoperative images. ConclusionsRoot canal preparation with PTN and TFA systems did not induce the formation of new dentinal microcracks.

Effectiveness of ProTaper, D‐RaCe, and Mtwo retreatment files with and without supplementary instruments in the removal of root canal filling material

To assess the efficacy of different retreatment rotary files in removing gutta-percha and endodontic sealer from canals. Ninety straight single-rooted premolars were prepared up to a size 30 and filled with gutta-percha and sealer and then randomly assigned to six retreatment groups (n = 15). Groups I, III, and V were retreated using rotary systems ProTaper Universal Retreatment (PTUR), D-RaCe, and Mtwo Retreatment, respectively. Groups II, IV, and VI were retreated using the additional instruments F4, size 40, .04 taper RaCe, and size 40, .04 taper Mtwo, respectively. The roots were split vertically, and images of the halves were obtained using a high-resolution scanner and evaluated with AutoCAD software to calculate the percentage of residual material. Data were analyzed with Kruskal-Wallis and Student-Newman-Keuls tests using a 5% significance cutoff (P < 0.05). There were no statistically significant differences (P > 0.05) between groups when additional instruments were used. The percentage of residual material was lowest in the PTUR group and was statistically significant only when compared to the D-RaCe system (P = 0.0038). All root canals had residual filling material after retreatment even when additional instruments were used.