Effects of shot-peening and atmospheric-pressure plasma on aesthetic improvement of Ti–Nb–Ta–Zr alloy for dental applications

Ti and Ti alloys are widely used for biomedical applications such as artificial joints and dental devices because of their good mechanical properties and biochemical compatibility. However, dental devices made of Ti and Ti alloys do not have the same color as teeth, so they are inferior to ceramics and polymers in terms of aesthetic properties. In a previous study, Ti–29Nb–13Ta–4.6Zr was coated with a white Ti oxide layer by heat treatment to improve its aesthetic properties. Shot-peening is a severe plastic deformation process and can introduce a large shear strain on the peened surface. In this study, the effects of shot-peening and atmospheric-pressure plasma on Ti–29Nb–13Ta–4.6Zr were investigated to form a white layer on the surface for dental applications.