Efecto de la esterilización en la resistencia a fatiga clínica de limas HyFlex CM, a nivel coronal y apical

Abstract

Aim: to compare cyclic fatigue resistance of new and sterilized HyFlex CM® files at apical and coronal levels. Methods: 180 files were divided in six groups (n=30): two of new files (A5, A11), two autoclaved once (B5, B11) and two autoclaved twice (C5, C11). Cyclic fatigue resistance was tested at 5 mm and at 11 mm from the tip. Weibull analysis was used to calculate the mean life, beta, and eta parameters. Results: New files will last significantly longer than files that were sterilized once or twice, with a probability of 72% and 61% at 5 mm from the tip and 75% and 72% at 11 mm from the tip, respectively. There was no statistically significant difference between the mean life of the files sterilized once or twice at 11 mm from the tip, but at 5 mm from the tip, files sterilized twice was significantly longer than those sterilized once, with a probability of 63%. Files will last significantly longer at 5 mm than 11 mm from the tip with a probability higher than 99%. Conclusions: HyFlex CM® files were more resistant to cyclic fatigue at the apical than the coronal levels. Unsterilized HyFlex CM® files were the most resistant.