The Efficacy of the WaveOne Reciprocating File System versus the ProTaper Retreatment System in Endodontic Retreatment of Two Different Obturating Techniques.

INTRODUCTION: This ex vivo study aimed to evaluate the efficacy of retreating GuttaCore (Dentsply Tulsa Dental Specialties, Tulsa, OK) and warm vertically condensed gutta-percha in moderately curved canals with 2 different systems: ProTaper Universal Retreatment (Dentsply Tulsa Dental) and WaveOne (Dentsply Tulsa Dental). METHODS: Eighty mesial roots of mandibular molars were used in this study. The mesiobuccal canals in each sample were prepared to length with the WaveOne Primary file (Dentsply Tulsa Dental). The canals were obturated with either a warm vertical approach or with GuttaCore and divided into 4 retreatment groups with the same mean root curvature: warm vertical retreated with ProTaper, warm vertical retreated with WaveOne, GuttaCore retreated with ProTaper, and GuttaCore retreated with WaveOne. The warm vertical groups were obturated using a continuous-wave technique of gutta-percha compaction, and the GuttaCore groups were obturated according to the manufacturer's instructions. After allowing sealer to set, each specimen was retreated with either the ProTaper Universal Retreatment files D1, D2, or D3 or with the WaveOne Primary file to the predetermined working length. The time taken to reach the working length was recorded. Instrument fatigue and failure were also evaluated. RESULTS: The post hoc 2-sample t tests showed that the overall mean total time taken to reach the working length for the warm vertical groups was significantly greater than that observed for the GuttaCore groups (mean = 87.11 vs 60.16 seconds, respectively), and the overall mean total time taken to reach the working length for WaveOne was significantly greater than that observed for ProTaper (99.09 vs 48.18 seconds, respectively). Two-way analysis of variance showed a significant main effect for both the type of experiment groups (F1,76 = 15.32, P = .0002) and the type of retreatments (F1,76 = 54.67, P < .0001). Also, the WaveOne Primary file underwent more separations than the ProTaper files. CONCLUSIONS: The WaveOne Primary file underwent more separations and was unable to remove gutta-percha as efficiently as the ProTaper Universal Retreatment files. Also, canals obturated with GuttaCore were retreated more efficiently and with fewer file separations than the canals obturated using continuous wave of warm gutta-percha.

Evaluation of the Efficacy of TRUShape and Reciproc File Systems in the Removal of Root Filling Material: An Ex Vivo Micro-Computed Tomographic Study.

INTRODUCTION: The purpose of this study was to evaluate the efficacy of TRUShape (Dentsply Tulsa Dental Specialties, Tulsa, OK) compared with the Reciproc file (VDW, Munich, Germany) in the removal of filling material from oval canals filled with 2 different sealers and differences in the working time. METHODS: Sixty-four mandibular canines with oval canals were prepared and divided into 4 groups (n = 16). Half of the specimens were filled with gutta-percha and pulp canal sealer (PCS), and the remainders were filled with gutta-percha and bioceramic sealer (BCS). The specimens were retreated using either the Reciproc or TRUShape files. A micro-computed tomographic scanner was used to assess filling material removal, and the time taken for removal was also recorded. Data were analyzed using the Kruskal-Wallis and Mann-Whitney U tests. RESULTS: The mean volume of the remaining filling material was similar when comparing both files (P ≥ .05). However, in the groups filled with BCS, the percentage of remaining filling material was higher than in the groups filled with PCS (P < .05). The reciprocating file allowed for faster filling removal than the TRUShape files (P < .05). Retreatment was faster in the groups that were filled with PCS compared with those filled with BCS (P < .05). CONCLUSIONS: There was no difference regarding the percentage of remaining filling material when comparing both files system; however, Reciproc was faster than TRUShape. BCS groups exhibited significantly more remaining filling material in the canals and required more time for retreatment. Remaining filling material was observed in all samples regardless of the technique or sealer used.

Glide Path Management with Single- and Multiple-instrument Rotary Systems in Curved Canals: A Micro-Computed Tomographic Study.

INTRODUCTION: Securing a reproducible glide path before instrumentation is recommended to maintain the original geometry of the root canal system and to prevent file separation. Mechanical glide path management systems have been introduced to expedite this step. The aim of this study was to compare apical transportation, canal volume increase, and working time during glide path management with ProGlider (PG; Dentsply Tulsa Dental Specialties, Tulsa, OK) and PathFiles (PF, Dentsply Tulsa Dental Specialties). METHODS: Forty curved mesial canals of mandibular molars were randomly allocated into 2 experimental groups (n = 20) according to the glide path management system: PG or PF. A glide path was achieved according to the manufacturers' protocol. Micro-computed tomographic analysis was performed to assess apical transportation at 1, 3, and 5 mm and volume increase. The time required to achieve the glide path was measured. RESULTS: The overall apical transportation mean values (± standard error) were 13.33 ± 3.37 µm for PG and 19.21 ± 4.4 µm for PF (P > .05). The mean (± standard error) volume increase values were 0.49 ± 0.06 mm(3) for PG and 0.48 ± 0.06 mm(3) for PF (P > .05). A statistically significant difference in the working time was found between the groups (P < .0001) where the mean (± standard error) values for time were 7.38 ± 1.73 seconds for PG and 20.61 ± 5.54 seconds for PF. CONCLUSIONS: Similar apical transportation and volume increase occurred during glide path management with PG single-file and PF multi-file systems; however, PG achieved glide path faster than PF.