Synchrotron radiation-based micro-computed tomographic analysis of apical transportation of different Nickel-Titanium rotary systems in curved root canals: An in vitro study.

BACKGROUND: In the last few decades, the availability of synchrotron sources has initiated revolutionary advances in X-ray imaging. AIMS: The study aimed to evaluate the incidence of apical transportation after root canal preparation with ProTaper Gold (PTG), Hyflex electro discharge machining (HEDM), Reciproc (RPC), and WaveOne Gold (WOG) using synchrotron radiation-based micro-computed tomographic (SR-µCT) analysis. MATERIALS AND METHODS: Forty mandibular molars were assigned to four experimental groups (n = 10) according to the file system used for the root canal preparation: Group 1: PTG (25/0.08), Group 2: HEDM (25/0.08), Group 3: RPC (25/0.08), and Group 4: WOG (25/0.07). The specimens were scanned on SR-µCT system before and after the root canal preparation. Apical transportation was assessed at 1, 2, 3, 4, and 5 mm section. STATISTICAL ANALYSIS: Two-way analysis of variance and Wilcoxon Mann-Whitney test was used. RESULTS: No significant difference was found between the groups. Transportation in the mesial direction was of greater magnitude than distal transportation for all the files systems. CONCLUSION: SR-µCT can be used as a reliable diagnostic tool for further implications.

Synchrotron radiation-based micro-computed tomographic analysis of dentinal microcracks using rotary and reciprocating file systems: An in vitro study.

BACKGROUND: Advances in both X-ray sources and X-ray optics have dramatically improved the feasibility of these techniques in various fields. AIMS: We aimed to evaluate the frequency of dentinal microcracks observed after root canal preparation with ProTaper Gold (PTG), Hyflex electrodischarge machining (HEDM), Reciproc (RPC), and WaveOne Gold (WOG) using synchrotron radiation-based micro-computed tomographic (SR-µCT) analysis. SUBJECTS AND METHODS: Forty mandibular molars were assigned to 4 experimental groups (n = 10) according to the file system used for the root canal preparation: Group 1: PTG (25/0.08), Group 2: HEDM (25/0.08), Group 3: RPC (25/0.08), and Group 4: WOG (25/0.07). The specimens were scanned on SR-µCT system before and after root canal preparation. The pre- and postoperative cross-sectional images (N = 183,200) of the mesial roots were screened to identify the presence of dentinal microcracks. The number of microcracks was determined as a percentage for each group. STATISTICAL ANALYSIS: There was no necessity of statistical analysis in the present study. The number of microcracks was determined as a percentage for each group. RESULTS: Among the four file systems tested, HEDM (0.9%) has shown a fewer number of new dentinal microcracks. CONCLUSIONS: SR-µCT can be used as a reliable diagnostic tool for further implications.