Department of Prosthodontics, School of Stomatology, Capital Medical University, Beijing, People's Republic of China.
Department of Prosthodontics, School of Stomatology, Capital Medical University, Beijing, People's Republic of China; Department of Stomatology, Electric Power Teaching Hospital, Capital Medical University, Beijing, People's Republic of China.
J Mech Behav Biomed Mater. 2023 Aug;144:105988. doi: 10.1016/j.jmbbm.2023.105988. Epub 2023 Jun 28.
The long-term successes of implant restorations rely on both appropriate osseointegration and robust soft tissue integration (STI). Numerous studies have reported that titanium dioxide nanotube (TNT) arrays formed by electrochemical anodization (EA) can promote early osteogenesis, but the mechanical stability of such modifications is often ignored and remains underexplored. In addition, relatively little research has been done on their effects on soft tissues integration. In this study, we developed mechanically robust TNT arrays using an optimized EA system. Subsequently, we immobilized a peptide, specifically D-amino K122-4, onto the anodized TNTs via polydopamine (PDA) films to enhance their mechanical properties. Surface morphology and composition were characterized by scanning electron microscopy (SEM), atomic force microscopy, and X-ray photoelectron spectroscopy. Mechanical properties, including the elastic modulus and hardness of TNTs modified Ti surfaces, were assessed using the nano-indention test. The adhesive strength of TNTs films to the substrate was measured using the nano scratch test. Furthermore, we evaluated the adhesion, spreading, and proliferation of human gingival fibroblasts (HGFs) and periodontal pathogenic bacteria such as Streptococcus mutans (S.m) and F. nucleatum (F.n) on the surface. Results showed that the elastic modulus, hardness, and adhesive strength of anodized TNTs were significantly enhanced by the incorporation of the D-amino K122-4 peptide. Live-dead staining and SEM observation suggested a decreased surface colonization by both bacterial species. The antibacterial rate of S.m and F. n was 81.5% and 71.7%, respectively, evaluated by colony counting method. Additionally, results of CCK8 assay showed that modified TNTs slightly stimulated HGFs attachment and proliferation while producing enhanced fluorescence of integrin β1 and F-actin, confirmed by laser confocal microscopy observation. Thus, D-amino K122-4 biofunctionalized TNTs present significantly improved mechanical properties, and the mechanically robust structures modulate HGFs proliferation and alignment, resulting in decreased bacteria growth. This novel strategy has the potential to create a surface coating for implants that exhibits superior mechanical robustness and enhanced surface-to-implant interactions.
种植体修复的长期成功依赖于适当的骨整合和强健的软组织整合（STI）。许多研究报告称，通过电化学阳极氧化（EA）形成的二氧化钛纳米管（TNT）阵列可以促进早期成骨，但这种修饰的机械稳定性往往被忽视，研究也相对较少。此外，关于它们对软组织整合的影响的研究也相对较少。在本研究中，我们使用优化的 EA 系统开发了机械坚固的 TNT 阵列。随后，我们通过聚多巴胺（PDA）薄膜将一种肽，即 D-氨基酸 K122-4，固定在阳极氧化的 TNT 上，以增强其机械性能。通过扫描电子显微镜（SEM）、原子力显微镜和 X 射线光电子能谱对表面形貌和组成进行了表征。通过纳米压痕试验评估了 TNT 修饰 Ti 表面的弹性模量和硬度等机械性能。通过纳米划痕试验测量了 TNT 薄膜与基底的附着强度。此外，我们评估了表面上人牙龈成纤维细胞（HGF）和牙周病原菌如变形链球菌（S.m）和产黑色素普雷沃菌（F.n）的粘附、铺展和增殖。结果表明，通过掺入 D-氨基酸 K122-4 肽，阳极氧化 TNT 的弹性模量、硬度和附着强度得到显著增强。活/死染色和 SEM 观察表明，两种细菌的表面定植都减少了。通过菌落计数法评估，S.m 和 F.n 的抑菌率分别为 81.5%和 71.7%。此外，CCK8 检测结果表明，修饰后的 TNTs 略微刺激了 HGFs 的附着和增殖，同时通过激光共聚焦显微镜观察证实了整合素 β1 和 F-肌动蛋白的荧光增强。因此，D-氨基酸 K122-4 生物功能化的 TNT 具有显著改善的机械性能，坚固的机械结构调节 HGFs 的增殖和排列，从而减少细菌的生长。这种新策略有可能为具有优异机械强度和增强表面与植入物相互作用的植入物创造表面涂层。
