The Study Of The Anticorrosive Ability Of Metal Brackets

Objective:The aim of this study was to test whether different methods of removing composite and F ion would influent the anticorrosive ability of brackets through comparing the ions released from metal brakets immersed in different buffers.Materials and Methods: comparing with the new brackets immersed in the artificial saliva without fluoride ion, new and recycled metal brackets with burn,silane and sandblast treatment were put into different immersion medias(artificial saliva with or without fluoride ion) over an extended time interval(1week and 4 weeks). The amount of nickel was determined by using an atomic absorption spectrophotometer.Results :1.the content of nickel ions released from the testing and comparing group are statistically;2.the nickel ions released from the burned group are significantly higher than salined and sandblasted groups,but not statistically in salined and sandblasted groups;3.the ions released from the new brackets immersed in artificial saliva with different fluoride content are statistically;4.more ions were found one month later in every group.Conclusion:1.metal bracket will be corrosived in artificial saliva and released metal ions;2.the three reconditioning methods will reduce the anticorrosion of metal bracket, and burn treatment is more serious than saline and sandblaste-treatment; 3.with the increase of immersion time,the brackets corrosive constantly, but the corrosived speed is gradually lower;4.the fluoride will aggravate the corrosion of bracket,and more ions will be released with the increase content of fluoride;5.although the ions detected in the experiment are all in safe range,we still need to notice the adverse effects of ions released from metal brackets.