Chemical and biological evaluation of different commercially available metal orthodontic brackets- An invitro study

Abstract

Aims: This invitro study was done to evaluate the chemical and biological properties of 4 brands of metal orthodontic brackets. Objectives: To analyse the chemical composition, the corrosion resistance, Nickel ion release and cytotoxicity of the orthodontic brackets. Methods: Four brands of orthodontic brackets namely: Group-1: Gemini(3M Unitek), Group-2: Ecoplus(Chirpans Orthodontics), Group-3: Monalisa(JJ Orthodontics), Group-4: Sapphire(Modern Orthodontics). Composition was analysed by Scanning- electron Microscopy with Energy Dispersive spectroscopy. Corrosion resistance was done by potentiodynamic polarisation in artificial saliva. Nickel ion release from the brackets was analysed by inductively coupled plasma mass spectrometry, at 24 hours, 7, 14, 28 days. Cytotoxicity of the brackets were analysed by Live- dead assay and MTT assay. Results: Gemini brackets offered better corrosion resistance and showed the least nickel release among all the groups. Cytotoxicity tests showed that Gemini is the least cytotoxic and Ecoplus is the most cytotoxic. Conclusion: The study concluded that Nickel ion is highest in Gemini brackets, but the nickel ion released from Gemini is the least among the four groups and showed better corrosion resistance and least cytotoxic.

Keywords

• Cytotoxicity
• Corrosion resistance
• Nickel ion
• Orthodontic brackets
• Scanning electron microscopy