Influência de esterilização nas propriedades mecânicas do instrumento Reciproc R25

Abstract

The aim of this study was to evaluate the influence of sterilization on the mechanical properties of Reciproc® R25 instrument (VDW, Munich, Germany). Bending tests were performed in 45° cantilever, rotating bending, stereomicroscopy and scanning electron microscopy. The stereomicroscopy assessed the tip angle, helix angle, taper and tip diameter of the instruments. The scanning electron microscopy evaluated the surface fracture after rotating bending test to check for possible differences between the groups. The bending test at 45° determined bending force to the original and autoclaved instruments, and rotating bending test time fatigue life. 4 groups were analyzed. Group 1 was composed of the instruments as received, the other groups were composed of sterile instruments 2, 4 and 6 times, each with 10 instruments, totaling a n of 40 instruments Reciproc® R25. The statistical test performed to compare the flexibility and time to fracture was the ANOVA with significance level of 5%. As for the characterization, instruments met the recommendation of ANSI / ADA 101. The scanning electron microscopy showed no difference in the finish and the fracture surface of the instruments as received and autoclaved. The data obtained in the flexural tests on 45 and rotating bending showed no statistically significant difference between the tested groups (p> 0.05). The autoclaving of Reciproc® R25 instruments did not interfere in their mechanical properties.