Surface modification techniques are often used to enhance the properties of Ti‐based materials as hard‐tissue replacements. While the microstructure of the coating and the quality of the interface between the substrate and coating are essential to evaluate the reliability and applicability of the surface modification. In this study, both a hydroxyapatite (HA) coating and a collagen‐hydroxyapatite (Col‐HA) composite coating were deposited onto a Ti‐6Al‐4V substrate using a biomimetic coating process. Importantly, a gradient cross‐sectional structure with a porous coating toward the surface, while a dense layer adjacent to the interface between the coating and substrate was observed in three‐dimensional (3D) from both the HA and Col‐HA coatings via a dual‐beam focused ion beam‐scanning electron microscope (FIB‐SEM). Moreover, the pore distributions within the entire coatings were reconstructed in 3D using Avizo, and the pores size distributions along the coating depth were calculated using RStudio. By evaluating the mechanical property and biocompatibility of these materials and closely observing the cross‐sectional cell‐coating‐substrate interfaces using FIB‐SEM, it was revealed that the porous surface created by both coatings well supports osteoblast cell adhesion while the dense inner layer facilitates a good bonding between the coating and the substrate. Although the mechanical property of the coating decreased with the addition of collagen, it is still strong enough for implant handling and the biocompatibility was promoted.

中文翻译：

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仿生涂层三维孔隙率梯度对其结合强度和细胞行为的影响

表面改性技术通常用于增强钛基材料作为硬组织替代物的性能。而涂层的微观结构和基材与涂层之间的界面质量对于评估表面改性的可靠性和适用性至关重要。在这项研究中，使用仿生涂层工艺将羟基磷灰石 (HA) 涂层和胶原蛋白-羟基磷灰石 (Col-HA) 复合涂层沉积在 Ti-6Al-4V 基材上。重要的是，通过双通道从 HA 和 Col-HA 涂层的三维 (3D) 中观察到具有朝向表面的多孔涂层的梯度横截面结构，同时在涂层和基材之间的界面附近观察到致密层束聚焦离子束扫描电子显微镜（FIB-SEM）。而且，使用 Avizo 在 3D 中重建整个涂层内的孔分布，并使用 RStudio 计算沿涂层深度的孔尺寸分布。通过评估这些材料的机械性能和生物相容性，并使用 FIB-SEM 密切观察横截面的细胞-涂层-基质界面，发现两种涂层产生的多孔表面很好地支持成骨细胞粘附，而致密的内层有利于促进成骨细胞的粘附。涂层与基材之间的良好结合。虽然涂层的机械性能随着胶原蛋白的加入而降低，但仍足以处理植入物，并促进了生物相容性。并使用 RStudio 计算沿涂层深度的孔径分布。通过评估这些材料的机械性能和生物相容性，并使用 FIB-SEM 仔细观察横截面的细胞-涂层-基质界面，发现两种涂层产生的多孔表面很好地支持了成骨细胞粘附，而致密的内层则促进了成骨细胞的粘附。涂层与基材之间的良好结合。虽然涂层的机械性能随着胶原蛋白的加入而降低，但仍足以处理植入物，并促进了生物相容性。并使用 RStudio 计算沿涂层深度的孔径分布。通过评估这些材料的机械性能和生物相容性，并使用 FIB-SEM 仔细观察横截面的细胞-涂层-基质界面，发现两种涂层产生的多孔表面很好地支持了成骨细胞粘附，而致密的内层则促进了成骨细胞的粘附。涂层与基材之间的良好结合。虽然涂层的机械性能随着胶原蛋白的加入而降低，但仍足以处理植入物，并促进了生物相容性。结果表明，由两种涂层产生的多孔表面很好地支持成骨细胞粘附，而致密的内层有利于涂层和基材之间的良好结合。虽然涂层的机械性能随着胶原蛋白的加入而降低，但仍足以处理植入物，并促进了生物相容性。结果表明，由两种涂层产生的多孔表面很好地支持成骨细胞粘附，而致密的内层有利于涂层和基材之间的良好结合。虽然涂层的机械性能随着胶原蛋白的加入而降低，但仍足以处理植入物，并促进了生物相容性。