In vitro biocompatibility of orthodontic brackets coated with TiO2-xNx thin film / 第二军医大学学报

ABSTRACT

Objective To evaluate the biocompatibility of orthodontic brackets coated with TiO2-xNx film , and to explore the effects of nitrogen-content and thickness of the film on the film biocompatibility. Methods We successfully prepared the TiO2-xNx film brackets samples. L929 cells were divided into film brackets group and control group. The film brackets group was further divided into the nitrogen content groups (argon/nitrogen gas flow ratio of 30: 1 , 30: 1. 5 , and 30: 2) and thickness groups (sputtering time were 30 , 60 , and 90 min). L929 cells were used to evaluate the biocompatibility of TiO2-xNx film of orthodontic brackets by the methods of cell adhesion , MTT assay and the lactate dehydrogenase LDH release assay. The experimental data were analyzed by SPSS 19. 0 Software , and the results were analyzed by one-way ANOVA. Results The L929 cells adhered and spread well on the surface of the brackets both in the film brackets group and the control group. Although the cell proliferation rates of the nitrogen content groups at 24 , 48 , and 72 h , and of the thickness group at 24 and 72 h were significantly different from that of the control group C0. 05). Conclusion The cytotoxicity of TiO2-xNx film is at grade 0 level , and nitrogen content and film thickness are relevant factors of the biocompatibility of L929 cells.