Effect of pH on the Corrosion Behaviour of Ti-6Al-4V alloy for Dental Implant Application in Fluoride Media

In the last few decades, titanium and its alloys have been developed in different areas of dentistry. The chemical properties of the oxide layer formed on the surface of titanium play an important role in the biocompatibility of the titanium implants and surrounding tissues. Generally, fluoride containing preparations have high fluoride concentration and pH range between 7.2 and 3.2. Since, fluorides are inimical to all reactive metals such as titanium especially in acidic medium, leads to corrosion due to the destruction of their passivity and loss of mechanical properties. The presence of fluoride ions in the electrolytic environments brings with it aggressiveness in the attack on titanium. This is due to the formation of complex titanium fluoride molecule, which is very stable and soluble in the electrolytic solution. Hence, the aim of the present work is to study the effect of pH 3.5, 5.0 and 7.0 on Ti-6Al-4V in artificial saliva solution containing 1% NaF (sodium fluoride). Electrochemical studies such as open-circuit potential (OCP) measurements, Potentiodynamic polarization and electrochemical impedance spectroscopy (EIS) were carried out in artificial saliva medium.