AIM: The purpose of this study was to evaluate cyclic fatigue of Profile Ni-Ti rotary instruments (PRIs) after dry heat sterilization and up to 10 times simulated clinical use. METHODOLOGY: Instruments of size 40-15 were used in a crown-down technique. Three groups were included in this study. In groups 1 and 2, each set of instruments was used in five and 10 canals, respectively. Group 3 was the control group. NaOCl at a concentration of 2.5% was used as an irrigant. Each set of instruments was sterilized before each use. RESULTS: The PRI size 40 demonstrated the lowest incidence of rotations to breakage. One-way analysis of variance and Turkey's HSD test showed statistically significant differences among different file sizes within each group. CONCLUSIONS: The results showed that dry heat sterilization and simulated clinical use in the presence of NaOCl did not lead to a decrease in the number of rotations to breakage of the files.
AIM: The purpose of this study was to evaluate cyclic fatigue of Profile Ni-Ti rotary instruments (PRIs) after dry heat sterilization and up to 10 times simulated clinical use. METHODOLOGY: Instruments of size 40-15 were used in a crown-down technique. Three groups were included in this study. In groups 1 and 2, each set of instruments was used in five and 10 canals, respectively. Group 3 was the control group. NaOCl at a concentration of 2.5% was used as an irrigant. Each set of instruments was sterilized before each use. RESULTS: The PRI size 40 demonstrated the lowest incidence of rotations to breakage. One-way analysis of variance and Turkey's HSD test showed statistically significant differences among different file sizes within each group. CONCLUSIONS: The results showed that dry heat sterilization and simulated clinical use in the presence of NaOCl did not lead to a decrease in the number of rotations to breakage of the files.