Decrease in the fatigue resistance of nickel-titanium rotary instruments after clinical use in curved root canals.

Maria Guiomar A Bahia; Vicente Tadeu Lopes Buono

doi:10.1016/j.tripleo.2004.10.013

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Decrease in the fatigue resistance of nickel-titanium rotary instruments after clinical use in curved root canals.

Maria Guiomar A Bahia·Vicente Tadeu Lopes Buono

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Abstract

OBJECTIVE: The changes in fatigue resistance of nickel-titanium rotary ProFile instruments after clinical use for shaping 10 curved molar root canals were evaluated in this study. STUDY DESIGN: Twenty-five sets of files #20, #25, and #30 and tapers .04 and .06 were divided into 2 groups, one with 10 sets of new files that were tested in a fatigue test bench device as a control. The other, experimental group, with 15 sets of clinically used files, was tested in the same device. The Student t test was employed to compare mean values of the measured parameters. RESULTS: A statistically significant decrease in the number of cycles to failure was determined for the clinically used files, as compared with the new ones. The fracture point was the same for all files tested. CONCLUSIONS: The clinical use of ProFile instruments for shaping curved canals reduces their fatigue resistance.

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Compressive Strength Dental Alloys Dental Instruments Dental Pulp Cavity Dental Stress Analysis Equipment Failure Equipment Reuse Humans Molar Nickel Root Canal Preparation Tensile Strength Titanium Journal Article Research Support, Non-U.S. Gov't

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Maria Guiomar A Bahia, Vicente Tadeu Lopes Buono. 2005. Decrease in the fatigue resistance of nickel-titanium rotary instruments after clinical use in curved root canals.. https://doi.org/10.1016/j.tripleo.2004.10.013

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