Abstract Surface coating on biomaterial implants remained a challenging task to researchers because of its simultaneous demand for various properties. Post-surgery problems like aseptic loosening and fibrous tissue encapsulation reduced the life of implants, thus threatening their durability and reliability. However, with the blessing of modern biomaterial science, scientists have coped up the challenge by developing bioactive, graded structure coating on bio-implants. Gradation in composition, structure, and porosity in coating showed a new path of success in this field. Thus, this review paper summarizes different functionally graded bioactive coatings, their deposition techniques, and characteristics to a large extent. It also emphasizes on the thrust area in this field and probable future direction, which can lead us near to success.

中文翻译：

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生物材料上的功能梯度涂层：批判性评论

摘要 生物材料植入物的表面涂层对研究人员来说仍然是一项具有挑战性的任务，因为它同时需要各种特性。无菌性松动和纤维组织包裹等术后问题会缩短植入物的使用寿命，从而威胁其耐用性和可靠性。然而，在现代生物材料科学的加持下，科学家们通过在生物植入物上开发具有生物活性的梯度结构涂层来应对挑战。涂层中成分、结构和孔隙率的渐变显示了该领域的新成功途径。因此，这篇综述论文在很大程度上总结了不同功能分级的生物活性涂层、它们的沉积技术和特性。它还强调了该领域的重点领域和可能的未来方向，这可以使我们接近成功。