title: The effect of electrical treatment on cyclic fatigue of NiTi instruments.
abstract: Dentists desire to use NiTi rotary instruments, which do not break inside the root canals of teeth, since the pieces from broken files are difficult to remove. The NiTi rotary instrument breakage is because of cyclic and torsional fatigue. Here the low-voltage (12 V) and high voltage (24 V) electrical treatments were used to enhance the cyclic fatigue of NiTi rotary instruments and increase their durability. In excremental groups, following electrical treatment samples of the NiTi instruments were rotated inside artificial root canals until they broke. Our results showed that electrical treatment with 12-V DC was effective in restoring NiTi instrument's resistance to cyclic fatigue. The scanning electron microscopy images and fractograph of samples exposed to 12-V electrical treatment showed a more regular texture over the surface with less dimpling on fractured site. These patterns can improve the super elasticity of tested devices during rotational movement, and delay the NiTi instruments separation in root canal preparations.
authors.affiliation: Departments of Ophthalmology &Visual Sciences and Biomedical Engineering, University of Wisconsin School of Medicine and Public health, Madison, Wisconsin.
authors.forename: Mohammad Ali
authors.initials: MA
authors.lastname: Saghiri
authors.forename: Armen
authors.initials: A
authors.lastname: Asatourian
authors.forename: Franklin
authors.initials: F
authors.lastname: Garcia-Godoy
authors.forename: James L
authors.initials: JL
authors.lastname: Gutmann
authors.forename: Mehrdad
authors.initials: M
authors.lastname: Lotfi
authors.forename: Nader
authors.initials: N
authors.lastname: Sheibani
mesh_terms: D003762:Dental Instruments; D004560:Electricity; D008422:Materials Testing; D008855:Microscopy, Electron, Scanning; D009532:Nickel; D013314:Stress, Mechanical; D013499:Surface Properties; D014025:Titanium
chemical_list: D009532:Nickel; D014025:Titanium
keywords: NCF; NiTi; cyclic fatigue; electric stimulation; rotary instrument