Background: Nanocoating stainless steel orthodontic brackets with a combination of copper and zinc oxide nanoparticles might alter the quantity of ions released from them in saliva. Methods: Stainless steel orthodontic brackets (Ormco Mini -Diamond series 0.22” slot, MBT prescription) (ORMCO CORP Glendora, California, USA) (n= 15 in each group) were coated with nanoparticles of Copper oxide (Group I) , Zinc oxide (Group II) and a combination of Copper oxide –Zinc oxide (Group III) nanoparticles using a spray pyrolysis method . The quantity of copper and zinc ions released from these three groups of brackets stored in artificial saliva and intubated at 370C was evaluated at 24hrs, 7th day, 14th day and 28th day using an atomic absorption spectrometer Inter group comparisons were performed with ANOVA followed by Post hoc Tuckey HSD and intragroup comparisons between different time intervals were performed with paired sample T test. . P value ≤ 0.05 was considered statistically significant. Results: The three groups of coated brackets released significantly more copper and zinc ions than the uncoated brackets. The copper oxide nanocoated and zinc oxide nano coated stainless steel orthodontic brackets released more copper and zinc ions when compared to the copper oxide - zinc oxide combination nanocoated orthodontic brackets and uncoated brackets. The highest surge of ion release was noted at the 7th day in all the three coated groups for both the ions evaluated Conclusion Brackets coated with a combination of copper oxide and zinc oxide nanoparticles demonstrated reduced quantity of copper and zinc ion release in artificial saliva.
Key words: atomic spectrophotometer, copper oxide nanoparticles, zinc oxide nanoparticles, copper ions, zinc ions , hybrid nanocoating