Nanolamellar Tantalum Interfaces in the Osteoblast Adhesion

Abstract

The design of topographically patterned surfaces is considered to be a preferable approach to influence cellular behavior in a controllable manner, in particular to improve the osteogenic ability in bone regeneration. In the present study, we fabricated nanolamellar tantalum (Ta) surfaces with lamella wall thicknesses of 40 nm and 70 nm. The cells attached onto nanolamellar Ta surfaces exhibited higher protein adsorption and expression of β1 integrin, as compared to the non-structured bulk Ta, which would facilitate the initial cell attachment and spreading. We thus as expected, observed a significantly enhanced osteoblast adhesion, growth, and alkaline phosphatase activity on nanolamellar Ta surfaces. However, the enhancement effects 2 of nanolamellar structures on the osteogenesis were weakened as the lamella wall thickness increases. The interaction between cells and Ta surfaces is examined through adhesion forces using atomic force microscopy. Our findings indicate that Ta surface with a lamella wall thickness of 40 nm possessed the highest stimulatory effect. The observed strongest adhesion force between cellattached tip and the Ta surface with 40 nm-thick lamella wall, encourages the much stronger binding of cells with the surface, and thus well-attached, stretched, and grown cells. We attributed this to the increase in available contact area of cells with the thinner-nanolamellar Ta surface. The increased contact area allows the enhancement of the cell-surface interaction strength, and thus the improved osteoblast adhesion. This study suggests that the thin-nanolamellar topography shows immense potential in improving the clinical performance of dental and orthopedic implants.

Implantable PEKK/tantalum microparticles composite with improved surface performances for regulating cell behaviors, promoting bone formation and osseointegration

“…The interaction of cells with the implant surface mainly depends on the surface topographical features as well as chemical composition [ 38 ]. Adhesion of osteogenic cells to the substrate is crucial for the cell proliferation as well as differentiation on the implant [ 39 ].…”

The progress on physicochemical properties and biocompatibility of tantalum-based metal bone implants

“…Therefore, Ta coating and Ta 2 O 5 thin film are the main forms of research on Ta in vitro. For Ta, topographic surface design, especially nanoscale chemistry and morphology, is conducive to protein adsorption, which will promote cell proliferation and differentiation, especially the enhancement of bone regeneration ability [77,78]. Quartz crystal microbalance (QCM-D) is a unique technique to measure the adsorption capacity and viscoelasticity of proteins on the metal surface, which can be used to infer the orientation and conformation changes of adsorbed proteins [79,80].…”

Fabrication and cellular interactions of nanoporous tantalum oxide

“…All these changes in the surface properties to form 25 nm sized nanopores favored fibroblast adhesion, proliferation and spreading, where surface properties of anodized nanofeatured materials, that is, surface chemistry, topography, hydrophobicity, and surface area, were influential on cellular functions (Toccafondi & Thorat, ; Wang et al, ; Zeng et al, ). Specifically, results showed increased surface roughness and higher surface areas for nanofeatured tantalum oxide surfaces compared to their nanosmooth counterparts, which provided more surface area for cellular interactions, and thus promoted enhanced cellular adhesion, proliferation and spreading on nanofeatured tantalum oxide surfaces (An et al, ; Stiehler et al, ; Wang et al, ). Additionally, the fact that NPT25 surfaces exhibited higher cellular density at 1, 3, and 5 days in vitro and higher cellular spreading compared to nonporous tantalum was in‐line with literature where hydrophilic surfaces promoted higher fibroblast adhesion and spreading compared to hydrophobic ones (Webb, Hlady, & Tresco, ).…”

“…Upon the nanoscale modification of tantalum, the surface properties, including surface chemistry, topography, energy, and so forth, would be altered, which in turn, improve cellular functions to enhance osseointegration with juxtaposed bone tissue (Balasundaram & Webster, ; Stiehler et al, ; Wang et al, ). For instance, An et al observed that osteoblast adhesion and proliferation on nanolamellar tantalum fabricated via equal channel angular pressing was higher compared to conventional tantalum having micrometer‐sized grains (An et al, ). Additionally, nanostructured tantalum coatings fabricated via ion implantation enhanced fibroblast adhesion in vitro , while reducing fibrous capsule formation and contracture in a mouse in vivo model (Park et al, ).…”