Back to Search
Start Over
Cyclic fatigue behavior of nickel-titanium dental rotary files in clinical simulated root canals.
- Source :
- Journal of the Formosan Medical Association; Apr2017, Vol. 116 Issue 4, p306-312, 7p
- Publication Year :
- 2017
-
Abstract
- <bold>Background/purpose: </bold>Dental rotary instruments can be applied in multiple conditions of canals, but unpredictable fatigue fracture may happen. This study evaluated the fatigue lives of two batches of nickel-titanium (NiTi) dental rotary files operating in clinically simulated root canals.<bold>Methods: </bold>Single-step cyclic fatigue tests were carried out to assess the performance of two batches of NiTi files (ProTaper and ProFile) in nine combinations of simulated canals (cylinder radii 5 mm, 7.5 mm, and 10 mm, and insertion angles 20°, 40°, and 60°). Two-step cyclic fatigue tests were carried out in simulated root canals with the same radius by using the following two sets of insertion angles: (20°, 40°), (20°, 60°), (40°, 20°), and (60°, 20°). Fracture surfaces were observed by scanning electron microscopy.<bold>Results: </bold>The single-step cyclic fatigue results showed that cyclic fatigue lives of the files decreased with increasing insertion angles or decreasing cylinder radius. The ProFile #25 .04 file was more fatigue resistant than the ProTaper F2 file. In two-step cyclic fatigue tests, the total fatigue lives were usually more than 100% when the files operated at a lower strain and then at a higher strain. By scanning electron microscopy, a larger area of fatigue striation corresponded to a longer fatigue life.<bold>Conclusion: </bold>Cyclic fatigue life can be influenced by the strains and geometries of files. The fatigue life was prolonged when the files operated at a lower strain and then at a higher strain. However, the fatigue life was shortened if the loading sequence was reversed. [ABSTRACT FROM AUTHOR]
- Subjects :
- ROOT canal treatment
TOOTH root diseases
FATIGUE risk factors
NICKEL-titanium alloys
ELECTRIC discharges
SCANNING electron microscopy
THERAPEUTICS
COMPARATIVE studies
DENTISTRY
MATERIALS testing
RESEARCH methodology
MEDICAL cooperation
NICKEL
RESEARCH
ROTATIONAL motion
TITANIUM
PRODUCT design
EVALUATION research
PHYSIOLOGIC strain
MEDICAL equipment reliability
EQUIPMENT & supplies
Subjects
Details
- Language :
- English
- ISSN :
- 09296646
- Volume :
- 116
- Issue :
- 4
- Database :
- Supplemental Index
- Journal :
- Journal of the Formosan Medical Association
- Publication Type :
- Academic Journal
- Accession number :
- 122102950
- Full Text :
- https://doi.org/10.1016/j.jfma.2016.06.002