Mechano-synthesized wollastonite-forsterite composite coatings on the plasma electrolytic oxidized Ti-6Al-4V alloy for dental implant

This study investigated an innovative approach for dental implant coatings by developing mechano-synthesized wollastonite-forsterite composite coatings (MC) on plasma electrolytic oxidized (PEO) Ti-6Al-4V alloy. The process involved PEO treatment using a pulsed DC power supply in an electrolyte solution of mono-calcium acetate and calcium glycerophosphate, followed by MC with mixed wollastonite (CaSiO3) and forsterite (Mg2SiO4) powders. After MC treatment, FESEM, EDS analysis, cross-section, XPS, Raman analysis, corrosion test, and an in vitro test for biocompatibility were performed. Comprehensive surface characterization revealed that wollastonite particles transformed into smaller needle-like shapes, while forsterite particles became slightly less uniform but retained their spherical shape. Higher wollastonite content resulted in greater pore filling with fine particles, whereas increased forsterite content led to fewer fine particles on the surface. Cross-sectional analysis showed Si concentration inside the pores. Notably, wollastonite-rich samples exhibited superior corrosion resistance and rapid initial apatite formation in simulated body fluid (SBF) studies. In contrast, forsterite-containing samples demonstrated more controlled and sustained bioactivity, forming magnesiumsubstituted hydroxyapatite over time. The novelty of this work lies in combining the bioactive properties of wollastonite and forsterite with enhanced PEO surface characteristics, resulting in coatings with tailored corrosion resistance and bioactivity profiles suitable for dental implant applications.