Introduction:
Introduction: Polyetheretherketone (PEEK) is considered as an alternative to titanium for dental implants due to its favourable properties. However, its bio-inert and hydrophobic surface limits osseointegration. This study investigated the effects of sandblasting and gold sputter coating on cell viability of fibroblasts in contact with PEEK.
Methods: Eighty PEEK discs (8mm diameter × 2mm height; PEEK Bio Solution) were divided into four groups: untreated (C), sandblasted (SB), gold sputter coated for 30s (G30), and sputter coated following sandblasting (SBG30). The specimens were sandblasted with 50µm alumina particles at 0.25MPa pressure for 10s (Duostar, BEGO). A gold sputter coater (Agar Scientific Ltd., Stansted) was used at 30mA for 30s against the G30 and SBG30 groups. Surface roughness (Sa and Ra) was assessed by optical profilometry (Profilm3D®, Filmetric) and analysed using MANOVA. Cell viability was evaluated using L929 fibroblasts via MTT assay at 2 and 7 days, analysed by two-way ANOVA. A pilot qualitative assessment was utilised to further examine cell proliferation.
Results: Sandblasting significantly influenced roughness (p<0.001) with SBG30 showing the highest values (Sa = 1.398 ± 0.920µm; Ra = 0.663 ± 0.185µm), while C showed the lowest (Sa = 0.386 ± 0.476µm; Ra = 0.180 ± 0.050µm). Cell viability significantly increased over time for all surface treatments (p<0.001, η² = 0.896), with SB showing the lowest values at 2 days (26.55 ± 9.53%), but the highest values at 7 days (136.04 ± 26.74%). These results with a pilot microscopy assessment revealed enhanced proliferation, suggesting a correlation between roughness and cell attachment. There was no interaction effect between the surface modification and the time (p<0.076, η² = 0.129).
Conclusions: Sandblasting, with or without gold coating, enhanced PEEK’s roughness into the optimal Sa and Ra, which was found to be associated with favourable fibroblast proliferation. These findings highlight sandblasting as an effective surface modification to improve the biological performance of PEEK in dental implant applications. In contrast, gold sputter coating on its own did not show any significant effects on cell viability.
