Comparative evaluation of cyclic fatigue resistance of four different nickel-titanium rotary files with different cross-sectional designs and alloy properties.

Abstract

OBJECTIVE:

The purpose of the present study was to evaluate the cyclic fatigue resistance of F6 SkyTaper (Komet Brasseler, Lemgo, Germany), K3XF (SybronEndo, Orange, CA, USA), new generation OneShape (Micro Mega, Besancon, France) and TRUShape 3D conforming files (Dentsply Tulsa Dental Specialties, Tulsa, OK, USA).

MATERIAL AND METHODS:

Ten instruments from each group were selected and allowed to rotate using a low-torque motor in a stainless steel block with 1.5 mm diameter, 3 mm radius of 60° angle of curvature at the manufacturer's recommended speed, and the number of cycles (NCF) from the beginning to the fracture was recorded. The data were analyzed using one-way ANOVA followed by post-hoc Tukey's test (P = 0.05).

RESULTS:

The ranking of the groups from the highest to the lowest NCF was as follows: F6 SkyTaper (959 ± 92), K3XF (725 ± 71), TRUShape (575 ± 84) and OneShape (289 ± 58). Statistically significant differences were detected between all groups (P < 0.05).

CONCLUSION:

Within the limitations of this study, F6 SkyTaper instruments presented the highest cyclic fatigue resistance among the tested instruments. The S-shaped cross-sectional design of F6 SkyTaper instruments could be the most important factor on the superior cyclic life span of these instruments.

CLINICAL RELEVANCE:

In endodontic practice, preferring the instruments with higher cyclic fatigue resistance would help to minimize the risk of instrument fractures; therefore especially during the preparation of curved canals, instruments with smaller core area and less cross-sectional metal mass, which could lead higher flexibility, can be proposed.

• Authors: Mehmet Emin Kaval, Ismail Davut Capar, Hüseyin Ertas, Bilge Hakan Sen
• Journal: Clinical oral investigations (Clin Oral Investig) Vol. 21 Issue 5 Pg. 1527-1530 (Jun 2017) ISSN: 1436-3771 [Electronic] Germany
• PMID: 27456784 (Publication Type: Comparative Study, Journal Article)

Chemical References

• Dental Alloys
• titanium nickelide
• Nickel
• Titanium

Topics

• Dental Alloys (chemistry)
• Dental Instruments
• Equipment Design
• Equipment Failure Analysis
• Materials Testing
• Nickel (chemistry)
• Root Canal Preparation (instrumentation)
• Surface Properties
• Titanium (chemistry)
• Torque