Improved osseointegration properties of hierarchical microtopographic/nanotopographic coatings fabricated on titanium implants

Abstract

BackgroundTitanium (Ti) implants are extensively used in reconstructive surgery and orthopedics. However, the intrinsic inertness of untreated Ti implants usually results in insufficient osseointegration. In order to improve the osteoconductivity properties of the implants, they are coated with hierarchical microtopographic/nanotopographic coatings employing the method of molecular layering of atomic layer deposition (ML-ALD).ResultsThe analysis of the fabricated nanostructured relief employing scanning electron microscopy, atomic force microscopy, and electron spectroscopy for chemical analysis clearly demonstrated the formation of the nanotopographic (<100 nm) and microtopographic (0.1–0.5 μm) titano-organic structures on the surface of the nanograined Ti implants. Subsequent coincubation of the MC3T3-E1 mouse osteoblasts on the microtopographic/nanotopographic surface of the implants resulted in enhanced osteogenic cell differentiation (the production of alkaline phosphatase, osteopontin, and osteocalcin). In vivo assessment of the osseointegrative properties of the microtopographically/nanotopographically coated implants in a model of below-knee amputation in New Zealand rabbits demonstrated enhanced new bone formation in the zone of the bone–implant contact (as measured by X-ray study) and increased osseointegration strength (removal torque measurements).ConclusionThe fabrication of the hierarchical microtopographic/nanotopographic coatings on the nanograined Ti implants significantly improves the osseointegrative properties of the intraosseous Ti implants. This effect could be employed in both translational and clinical studies in orthopedic and reconstructive surgery.

Application of inorganic nanomaterials in bone tissue engineering and regenerative medicine

“…然 而, 钛金属自身具有较高的生物惰性, 容易被体内的 纤维组织包覆, 从而导致材料与骨组织分离, 造成移 植失败. 研究人员通过在钛合金表面进行纳米涂层 来解决这一问题, 此方法极大地改善了钛金属的生 物惰性, 使其更适应成骨细胞的外环境 [103,104] . Ren等 人 [105] 合成了具有抑菌性的钛植入复合材料, 该复合 材料具有多级结构, 将层状钛酸组成的网状结构组 装在钛金属表面, 进而在层状结构的层间镶嵌银纳 米颗粒, 形成钛酸-银纳米颗粒-钛酸的多层结构, 同 时具有优良的抑菌性能和较好的生物相容性, 在可 植 入 生 物 材 料 领 域 具 有 广 阔 的 应 用 前 景 .…”

Template Electrochemical Synthesis of Hydroxyapatite on a Titania–Silver Composite Surface for Potential Use in Implantology

“…This effect is due to faster osteoblast differentiation by blocking the drift along the surface with higher roughness. However, surfaces with various reliefs give different responses, which makes it impossible to unambiguously quantify the engraftability nature [10][11][12][13][14][15][16][17][18][19][20][21][22].…”

<p>Enhanced Osseointegration of Titanium Implants by Surface Modification with Silicon-doped Titania Nanotubes</p>

“…7,8 For example, well-organized topographic cues at nano/microscales could improve biocompatibility and promote bone formation, which are crucial for successful osseointegration between implant and bone. 9,10 Thus, implants modified with nano-/micro-structured surface, being capable of regulating cell behaviors, are very promising for orthopedic applications. 11 For example, the filopodia of cells can go into the pore of nanotubes to form a locked-in cell structure for bone ingrowth.…”