ZrO₂ Ceramic without and with Fullerene C₆₀ Films: In Vitro Direct-Contact Model Using E. coli and S. aureus Bacteria

Area of Science:

• Biomaterials Science
• Surface Engineering
• Microbiology

Background:

• Zirconia is a robust, bioinert material for dental implants, but lacks inherent antibacterial activity.
• Inflammation affects 3-5% of dental implants, highlighting the need for improved antibacterial properties.
• Maintaining beneficial oral bacteria is essential, necessitating a moderate antibacterial effect.

Purpose of the Study:

• To investigate the antibacterial efficacy of fullerene C60 films on zirconia against Staphylococcus aureus.
• To evaluate the impact of nitrogen plasma treatment and tribomechanical loading on fullerene C60-coated zirconia.
• To assess the antibacterial properties of tribomechanically patterned yttria-stabilized zirconia without fullerene C60.

Main Methods:

• Fabrication and characterization of different fullerene C60 films on zirconia substrates.
• Application of nitrogen plasma treatment and tribomechanical surface patterning.
• Quantitative assessment of antibacterial activity against Gram-positive Staphylococcus aureus using log reduction.

Main Results:

• Zirconia with fullerene C60 film showed an 85.8% reduction in Staphylococcus aureus.
• Plasma treatment and tribomechanical loading of fullerene C60 films further modulated antibacterial effects.
• Tribomechanically patterned zirconia without fullerene C60 demonstrated a 70.46% increase in antibacterial efficacy.

Conclusions:

• Fullerene C60 films and tribomechanical surface modifications significantly enhance the antibacterial activity of zirconia.
• These surface treatments offer a promising strategy for developing improved dental implant materials with controlled antibacterial properties.
• The findings suggest a potential to reduce implant-associated inflammation while preserving beneficial oral microflora.