Polyether-ether-ketone (PEEK) is one of the most common materials used for load-bearing orthopaedic devices due to its radiolucency and favorable mechanical properties. However, current smooth-surfaced PEEK implants can lead to fibrous encapsulation and poor osseointegration. This study compared the in vitro and in vivo bone response to two smooth PEEK alternatives: porous PEEK and plasma-sprayed titanium coatings on PEEK. MC3T3 cells were grown on smooth PEEK, porous PEEK, and Ti-coated PEEK for 14 days and assayed for calcium content, osteocalcin, VEGF and ALP activity. Osseointegration was investigated by implanting cylindrical implants into the proximal tibiae of male Sprague Dawley rats for 8 weeks. Bone-implant interfaces were evaluated using μCT, histology and pullout testing. Cells on porous PEEK surfaces produced more calcium, osteocalcin, and VEGF than smooth PEEK and Ti-coated PEEK groups. Bone ingrowth into porous PEEK surfaces was comparable to previously reported porous materials and correlated well between μCT and histology analysis. Porous PEEK implants exhibited greater pullout force, stiffness and energy-to-failure compared to smooth PEEK and Ti-coated PEEK, despite Ti-coated PEEK exhibiting a high degree of bone-implant contact. These results are attributed to increased mechanical interlocking of bone with the porous PEEK implant surface. Overall, porous PEEK was associated with improved osteogenic differentiation in vitro and greater implant fixation in vivo compared to smooth PEEK and Ti-coated PEEK. These results suggest that not all PEEK implants inherently generate a fibrous response and that topography has a central role in determining implant osseointegration.

聚醚醚酮（PEEK）由于其射线不透性和良好的机械性能，是用于承重骨科器械的最常见材料之一。然而，当前表面光滑的PEEK植入物可导致纤维包封和不良的骨整合。这项研究比较了体内和体外骨骼对两种光滑PEEK替代品的反应：多孔PEEK和PEEK上的等离子喷涂钛涂层。MC3T3细胞在光滑的PEEK，多孔的PEEK和涂有钛的PEEK上生长14天，并测定钙含量，骨钙素，VEGF和ALP活性。通过将圆柱状植入物植入雄性Sprague Dawley大鼠的胫骨近端8周来研究骨整合。使用μCT，组织学和拔出测试评估骨-植入物界面。与光滑的PEEK和钛涂层的PEEK组相比，多孔PEEK表面上的细胞产生更多的钙，骨钙素和VEGF。骨向PEEK表面的向内生长与以前报道的多孔材料相当，并且在μCT和组织学分析之间有很好的相关性。多孔PEEK植入物表现出更大的拔出力，尽管光滑的PEEK和Ti涂层的PEEK表现出高度的骨-植入物接触性，但与光滑的PEEK和Ti涂层的PEEK相比，它具有更高的刚度和破坏能量。这些结果归因于骨骼与多孔PEEK植入物表面的机械互锁增加。总体而言，多孔PEEK与成骨分化改善有关与光滑的PEEK和钛涂层的PEEK相比，在体外具有更好的体内植入物固定能力。这些结果表明，并不是所有的PEEK植入物都会固有地产生纤维反应，并且形貌在确定植入物的骨整合方面起着核心作用。