Evaluation of the resistance to cyclic fatigue among ProTaper Next, ProTaper Universal, and Vortex Blue rotary instruments.

Abstract

INTRODUCTION:

The purpose of this study was to compare the fracture resistance to cyclic fatigue of ProTaper Next (PTN; Dentsply Tulsa Dental Specialties, Tulsa, OK), ProTaper Universal (PTU, Dentsply Tulsa Dental Specialties), and Vortex Blue (VB, Dentsply Tulsa Dental Specialties) rotary instruments.

METHODS:

Twenty instruments each of PTN X1-X5, PTU S1-F5, and VB 20/04-50/04 were rotated until fracture in a simulated canal of 90° and a 5-mm radius using a custom-made testing platform. The number of cycles to fracture (NCF) was calculated. Weibull analysis was used to predict the maximum number of cycles when 99% of the instrument samples survive.

RESULTS:

VB 20/04-30/04 had significantly higher NCF than PTU S1-F5 and PTN X1-X5. VB 35/04-45/04 had significantly higher NCF than PTU S2-F5 and PTN X2-X5. PTN X1 had higher NCF than PTU S1-F5. PTN X2 had higher NCF than PTU F2-F5. The Weibull distribution predicted the highest number of cycles at which 99% of instruments survive to be 766 cycles for VB 25/04 and the lowest to be 50 cycles for PTU F2.

CONCLUSIONS:

Under the limitations of this study, VB 20/04-45/04 were more resistant to cyclic fatigue than PTN X2-X5 and PTU S2-F5. PTN X1 and X2 were more resistant to cyclic fatigue than PTU F2-F5. The Weibull distribution appears to be a feasible and potentially clinically relevant model to predict resistance to cyclic fatigue.

• Authors: Harrison H Nguyen, Hanson Fong, Avina Paranjpe, Natasha M Flake, James D Johnson, Ove A Peters
• Journal: Journal of endodontics (J Endod) Vol. 40 Issue 8 Pg. 1190-3 (Aug 2014) ISSN: 1878-3554 [Electronic] United States
• PMID: 25069931 (Publication Type: Comparative Study, Journal Article)
• Copyright: Copyright © 2014 American Association of Endodontists. All rights reserved.

Chemical References

• Dental Alloys
• titanium nickelide
• Nickel
• Titanium

Topics

• Algorithms
• Dental Alloys (chemistry)
• Equipment Design
• Equipment Failure
• Humans
• Materials Testing
• Nickel (chemistry)
• Root Canal Preparation (instrumentation)
• Rotation
• Stress, Mechanical
• Surface Properties
• Survival Analysis
• Time Factors
• Titanium (chemistry)