Preparation And Properties Study Of Orthodontic Brackets Coated With N-doped TiO_2-xN_x Thin Film

In orthodontic treatment, fixed appliance has been widely used for its efficiency and precision in clinical. But there are complications in orthodontic treatment,for example,enamel decalcification, gingivitis, periodontitis. Doctors pay much attention to these problems.In this study,we prepared orthodontic brackets coated with TiO2-xNx in the hope of playing its antimicrobial performance by the photocatalysis and improving its properties of surface, and then reducing bacterial adherence and incidence of complications.methods Orthodontic brackets coated with TiO2-xNx thin film was prepared by RF magnetron sputtering. The crystal structure, surface morphology were characterized by XRD, SEM, the adhesion strength, surface roughness and coefficient of friction were studied by AFM and Multifunctional Tester for surface. And the perofrmance of antibacteria of the brackets coated with TiO2-xNx thin film was also sutdied.results1.Orthodontic brackets coated with TiO2-xNx thin film have been prepared.2. The TiO2-xNx thin film coated on brackets is anatase phase.The surface is compact and smooth, thickness is about 500nm, the grain size is around 30nm, nitrogen content is 0.13%.3.The film has good adhesion strength..The surface of brackets can improve remarkably the surface roughness. The coefficient of static friction and coefficient of kinetic friction of Orthodontic brackets coated with TiO2-xNx thin film are lower than Orthodontic brackets without TiO2-xNx.4. The bacteria assay reflected to the antibacterial effect,95.19% of streptococcus mutans,91.00% of lactobacillus,69.44%of actinomyces viscosus, and 98.86% of candida albicans.conclusion1.Orthodontic brackets coated with TiO2-xNx thin film improve surface properties.2.Orthodontic brackets coated with TiO2-xNx thin film also show good photocatalysis and antibacterial effect.