Formation of TiO₂nanotubular layers on Ti-6Al-4V based dental implants for inhibiting biofilm growth

Modification of Ti-6Al-4V through electrochemical anodization method has been investigated on the purpose of generating TiO₂nanotube arrays (TiNTAs) on the surface of Ti-6Al-4V films. The as-anodized samples were calcined in an atmospheric furnace at various temperatures, in the range of 500-800°C. The evaluation of biofilm inhibition was performed by an in vitro method with Streptococcus mutans as a bacterium model. FE-SEM imaging confirmed the successful formation of TiO₂nanotube arrays while XRD results implied a phase transformation from anatase to rutile when the calcination temperature was around 600-650°C with average crystallite size of 18 nm. Calcination temperature is one of determining factors in the adjustment of crystallinity and morphology of TiO₂, which in turn affects its capability to suppress biofilm formation. This study revealed that the best sample for biofilm inhibition was calcined at 600°C with a crystallite phase of mostly anatase. This sample managed to improve antibacterial activity of up to five times as compared to the unmodified Ti-6Al-4V. The output of this study is expected to give some insight on a promising alternative for preventing the formation of harmful biofilm on dental implants.