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Introduction: The aim of this study was to evaluate the transportation and centring ability of five different rotary and reciprocating file systems with different metallurgical properties and surface treatments in curved root canals. Methods: Using the instrumentation equipment in utilisation, fifty mesiobuccal round canals of upper molars with a cuvature of 25–40° were divided into five experimental groups (n = 12): ProTaper Next (PTN), TruNatomy (TRN), XP-endo Shaper (XPS), Reciproc Blue (RCB), and Reciproc (RC). Five millilitres of 2.5% NaOCl were utilised in per root canal during instrumentation. The final irrigation schedule called for irrigation with NaOCl and 15% ethylenediaminotetraacetic acid. In order to assess the samples' transportation and centering abilities at three canal levels, micro-CT scanning was done on them both before and after instrumentation. A one-way ANOVA test along with a corresponding post hoc test was used to examine the data. Results: In comparison to the other methods, RCB resulted in notably greater canal transportation overall (p0.05). Between the other methods, there were no appreciable differences (p>0.05). When compared to the RC and RCB procedures, the PTN's ability to remain inside the root canal's core axis was noticeably superior (p=0.046, p=0.017). All methods produced comparable apical transportation and centring ability in the apical third (p>0.05). Compared to alternative methods, the RCB considerably increased canal transportation in the middle and cervical portions of the canal (p0.05). Conclusions: Under the limitations of this study, all tested techniques had similar transportation and centring abilities in the apical part of the canal. However, overall results and those in the middle and coronal parts of the canal indicated that reciprocating instruments resulted in more canal transportation and less centred preparations.