Direct Laser Interference Patterning (DLIP) on PEEK Coating for Biomedical and Dental Applications

Objective Polyether ether ketone (PEEK) is widely recognized for its biocompatibility and mechanical stability, making it a promising coating material for dental implants. However, unmodified surfaces may lack optimal properties for osseointegration and antibacterial resistance. Direct laser interference patterning (DLIP) is an advanced technique for introducing controlled micro- and nanoscale surface features to enhance implant performance. This study aims to investigate the surface characteristics, antibacterial effect, and biocompatibility of DLIP-functionalized PEEK coatings electrophoretically deposited on 316L stainless steel (SS). Materials and Methods PEEK was deposited onto 316L SS substrates via electrophoretic deposition and subsequently functionalized using DLIP to create periodic surface patterns with spatial periods of 1, 1.5, and 2 µm. The modified surfaces were characterized using scanning electron microscopy, contact angle (wettability), and surface roughness measurements. Antibacterial activity was assessed using the turbidity method against Escherichia coli. Biocompatibility was evaluated via MG-63 osteoblast-like cell viability analysis. Results The DLIP-functionalized PEEK surface with a 1.5-µm spatial period exhibited the most favorable surface features, with a contact angle of 92 ± 1° and surface roughness of 2.04 ± 0.03 µm. This configuration significantly inhibited E. coli growth and achieved 80% cell viability, indicating enhanced antibacterial properties and biocompatibility. Conclusion DLIP is an effective technique for functionalizing PEEK coatings, improving key surface characteristics that support antibacterial activity and osteoblast cell compatibility. Among the tested configurations, a 1.5-µm spatial period yielded the most promising results. Clinical Relevance This study supports the application of DLIP-functionalized PEEK coatings for dental implants, offering a novel and translatable surface.