Dental and Medical Problems

Dent. Med. Probl.
Index Copernicus (ICV) – 109.28, MNiSW – 11
Rejection rate – 43.33%
License – Creative Commons: Attribution 3.0 Unported (CC BY 3.0)
ISSN 1644-387X (print),   ISSN 2300-9020 (online)
Periodicity – quarterly

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Dental and Medical Problems

2018, vol. 55, nr 4, October-December, p. 389–394

doi: 10.17219/dmp/95201

Publication type: original article

Language: English

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Creative Commons BY-NC-ND 3.0 Open Access

The influence of the manufacturing process of rotary files on the shaping of L-shaped canals

Wpływ procesu wytwarzania rotacyjnych pilników endodontycznych na opracowanie kanału w kształcie litery L

Mateusz Radwański1,A,B,C,D,F, Michał Łęski1,A,E,F, Halina Pawlicka1,E,F

1 Department of Endodontics, Medical University of Lodz, Poland


Background. The nickel-titanium alloy used in the production of nickel-titanium files contains approx. 56% nickel and 44% titanium by weight. To improve the properties of nickel-titanium files, the manufacturers introduce some innovations in the production process. Their purpose is primarily to decrease the stiffness of the instruments while increasing the resistance to cyclic fatigue, which reduces the risk of file separation. One of the most popular processes is the heat treatment of the nickel-titanium alloy.
Objectives. The aim of the research was to determine the influence of the manufacturing process of rotary files on the shaping of L-shaped canals.
Material and Methods. Fifty L-shaped resin canals were instrumented (10/group) with ProTaper Universal ®, ProTaper Next®, Hyflex CM®, Hyflex EDM®, or WaveOne Gold® files, with the same apical size of 25. Each L-shaped resin canal was photographed both before and after instrumentation. Differences between the change of the working length and apical transportation were analyzed statistically.
Results. The smallest mean loss of the working length was observed after instrumentation with Hyflex CM files. Statistically significant differences in the working length were found between ProTaper Universal and Hyflex CM (p = 0.0032), ProTaper Universal and Hyflex EDM (p = 0.021), and ProTaper Universal and WaveOne Gold (p = 0.0112) files. The lowest apical transportation was noted in the case of WaveOne Gold files. In terms of apical transportation, statistically significant differences were observed between ProTaper Universal and WaveOne Gold files (p = 0.0254). Shaping Lshaped canals with the ProTaper Universal file system resulted in the greatest changes in the working length (x = 0.35 mm) and apical transportation (x = 0.034 mm).
Conclusion. The study, with its limitations, shows that in the files whose nickel-titanium alloy was subjected to a thermal treatment process, a smaller loss of the working length and lower values of apical transportation were observed.

Key words

nickel-titanium rotary files, canal shaping, resin blocks

Słowa kluczowe

niklowo-tytanowe rotacyjne pilniki endodontyczne, opracowanie kanału, bloki żywicowe

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