Effects of sterilization and disinfection procedures on the corrosion of orthodontic ligature cutters.

OBJECTIVE The objective of our study was to investigate the corrosion resistance of orthodontic ligature cutters subjected separately to two different sterilization procedures, namely, autoclaving and chemical disinfection with main focus on the cutting section of each instrument. MATERIALS AND METHODS Twenty-four ligature cutters were obtained from three different manufacturers: Hu-Friedy, ETM, and Nadir & Co. The study included a control group (G0) and four experimental groups (G1-4). G1 was subjected to 50 autoclave sterilization cycles. G2, G3, and G4 were subjected to 50 chemical disinfection cycles using, respectively, Peridiol E, Hexanios G+R, and Steranios 2%. Manufacturer recommendations were followed. The instruments' blades were studied via SEM and X-ray microanalysis (EDX spectrum). RESULTS These cutters have inserts made from various resistant alloys. SEM micrographs revealed different forms of corrosion depending on whether autoclaving or chemical disinfectant sterilization procedures were used, and depending on the alloys present. Chemical disinfection is more aggressive than autoclave sterilization, and is responsible for localized corrosion in the form of pitting. This is more detrimental to the lifespan of orthodontic cutters. CONCLUSION Sterilization/disinfection procedures should be adapted to the chemical profile of the metal alloys present. Recommendations for use published by instrument manufacturers must be followed.

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