Surface Modification of Polyetherketoneketone for High Resin Adhesion Strength

ABSTRACT Polyetherketoneketone (PEKK) has garnered significant interest as a dental implant material. However, its low surface hydrophilicity and free energy result in weak shear bond strength (SBS) to dental resins. Therefore, this study aims to enhance the SBS between PEKK and dental resins by increasing its surface free energy through chemical surface modification techniques. The PEKK specimens were sulfonated using concentrated sulfuric acid to generate a three‐dimensional porous surface structure. Subsequently, sequential modifications were performed: ethylenediamine amination, sodium borohydride reduction, and UV‐induced acrylic acid grafting. Dental resin was bonded to the modified surfaces, and the specimens underwent 24 h aging in distilled water at 37°C before shear bond strength (SBS) testing. The results indicated that the surface modification significantly enhanced the shear bond strength between PEKK and dental resin, along with a marked improvement in surface hydrophilicity.