Comparative Analysis of Bacterial Adhesion on Titanium Implants Treated with Plasma Electrolytic Oxidation

Titanium implants are widely used in dentistry and orthopedics due to their excellent biocompatibility and mechanical properties. However, bacterial adhesion and subsequent biofilm formation remain a significant challenge, potentially leading to implant failure. Plasma electrolytic oxidation (PEO) is a surface modification technique that enhances implant surface properties, potentially reducing bacterial adhesion.

A total of 40 titanium implants were divided into two groups: untreated implants (Group A) and PEO-treated implants (Group B). The PEO process was performed in an electrolyte solution to create a porous oxide layer on the implant surface. Both groups were incubated with Staphylococcus aureus and Escherichia coli bacterial suspensions under controlled conditions. Bacterial adhesion was quantified using a colony-forming unit (CFU) assay. The surface roughness and wettability of the implants were analyzed using profilometry and contact angle measurements, respectively. Statistical analysis was performed using the t-test, with significance set at P < 0.05.

Group B (PEO-treated implants) exhibited significantly reduced bacterial adhesion compared to Group A (untreated implants). The CFU count for S. aureus was reduced by 65% (mean CFU: 1.2 × 10⁵ for Group A vs. 4.2 × 10⁴ for Group B; P < 0.01). Similarly, the adhesion of E. coli was reduced by 58% (mean CFU: 1.5 × 10⁵ for Group A vs. 6.3 × 10⁴ for Group B; P < 0.01). Surface roughness and wettability improved in Group B, with a significant decrease in contact angle, indicating enhanced hydrophilicity.

The PEO treatment of titanium implants significantly reduces bacterial adhesion by modifying surface properties such as roughness and wettability. This surface modification technique shows promise in improving implant longevity and reducing the risk of infection.