Key topographic parameters driving surface adhesion of Porphyromonas gingivalis

Area of Science:

• Biomaterials Science
• Surface Engineering
• Microbiology

Background:

• Dental implant failure is often caused by peri-implantitis, linked to bacterial biofilm formation.
• Bacterial adhesion to implant surfaces is critically influenced by surface micro-/nano-topographies.
• Understanding surface texture parameters is crucial for predicting and mitigating bacterial adhesion.

Purpose of the Study:

• To investigate the relationship between femtosecond laser-induced surface topographies on Ti6Al4V and *Porphyromonas gingivalis* adhesion.
• To identify key surface texture parameters that accurately describe bacterial interaction with laser-modified titanium surfaces.
• To explore the potential for designing biofunctional dental implants with tailored surface properties.

Main Methods:

• Mirror polished Ti6Al4V titanium alloy samples were treated with a femtosecond laser (1030 nm) with varied parameters.
• Three-dimensional surface topographies were captured using focal variation microscopy.
• Surface parameters were analyzed using MountainsMap software, and *P. gingivalis* adhesion was quantified in vitro.

Main Results:

• Standard surface roughness parameter (Sa) was insufficient to characterize the complex laser-induced topographies and their effect on bacterial adhesion.
• Specific parameters, including Sku (surface kurtosis), furrow density, and mean furrow depth, showed strong correlations with *P. gingivalis* adhesion.
• These findings highlight the inadequacy of traditional roughness measures for predicting bacterial interaction on advanced surface textures.

Conclusions:

• Femtosecond laser texturing offers a method to engineer titanium surfaces with controlled topography for influencing bacterial adhesion.
• Advanced surface parameters beyond simple roughness are essential for accurately predicting bacterial interaction with implant materials.
• This research provides a foundation for developing next-generation dental implants with enhanced biofunctional properties through precise surface design.