Innovative Ag–CaP–ZrO₂ Coatings on Ti6Al4V: A Multifunctional Strategy to Improve the Durability of Dental Implants

Introduction:
Titanium alloy Ti6Al4V is widely applied in dental implantology due to its high mechanical strength and biocompatibility. However, its biologically inert surface limits osteointegration and provides insufficient protection against bacterial adhesion, which may compromise long-term clinical outcomes. Developing multifunctional coatings is therefore essential to overcome these limitations.

Methods:

A composite coating composed of calcium phosphate (CaP) and silver (Ag), reinforced with zirconium oxide (ZrO₂), was deposited on Ti6Al4V substrates using an immersion technique. Morphological and structural characteristics were assessed by SEM/EDS and XRD. Electrochemical performance was evaluated in artificial saliva using electrochemical impedance spectroscopy (EIS) and potentiodynamic polarization. Antibacterial activity against Staphylococcus aureus and cytocompatibility with MG-63 osteoblast-like cells after 72 h of culture were also investigated.

Results:

The coatings exhibited a homogeneous and stable morphology. Electrochemical analyses showed a marked improvement in corrosion resistance, with a polarization resistance (Rp) of 861,652 Ω·cm² for Ti6Al4V–CaP/Ag,Zr compared to 492,253 Ω·cm² for bare Ti6Al4V and 232,086 Ω·cm² for CaP-only coatings. Silver incorporation reduced bacterial adhesion by approximately 75–80% , while cell viability remained above 80%, confirming the absence of cytotoxic effects.

Conclusion:
Ag–CaP–ZrO₂ coatings combined bioactivity, antibacterial activity, and superior corrosion resistance. These multifunctional surfaces represent an innovative and effective approach to enhancing osteointegration and improving the long-term clinical performance of dental implants.