A physical vapor deposition method for controlled evaluation of biological response to biomaterial chemistry and topography

Abstract

The purpose of this study was to characterize a technique to effectively mask surface chemistry without modifying surface topography. A thin layer of titanium was deposited by physical vapor deposition (PVD) onto different biomaterial surfaces. Commercially pure titanium disks were equally divided into three groups. Disks were either polished to a mirror finish, grit blasted with alumina particles, or grit blasted and subsequently plasma sprayed with a commercial grade of hydroxyapatite (HA). A subgroup of each of these treatment types was further treated by masking the entire disk surface with a thin layer of commercially pure titanium deposited by PVD. A comparison of surface topography and chemical composition was carried out between disks within each treatment group. Canine marrow cells were seeded on all disk surfaces to determine the stability of the PVD Ti mask under culture conditions. The PVD process did not significantly alter the surface topography of any samples. The thin titanium layer completely masked the underlying chemistry of the plasma sprayed HA surface and the chemistry of the plasma vapor deposited titanium layer did not differ from that of the commercially pure titanium disks. Aliquots obtained from the media during culture did not indicate any significant differences in Ti concentration amongst the Ti and Ti-masked surfaces. The PVD application of a Ti layer on HA coatings formed a stable, durable, and homogenous layer that effectively masked the underlying surface chemistry without altering the surface topography.

Improving Biocompatibility of Implantable Metals by Nanoscale Modification of Surfaces: An Overview of Strategies, Fabrication Methods, and Challenges

“…For example, PVD was adopted to modify titanium with different nanotopographical coatings for in vitro studies of the effects of surface roughness on focal adhesion contact formation by fibroblasts 122. Similarly, titanium layers were deposited by PVD on textured titanium and hydroxyapatite to evaluate the effects of surface chemistry and topography on the cellular and/or tissue response 123. Although not nanometric in scale, PVD‐deposited titanium/silver coatings proved to increase the antibacterial properties of titanium 124.…”

Development of a biointegrated mandibular reconstruction device consisting of bone compatible titanium fiber mesh scaffold

“…These coatings, which include calcium phosphate, provide a bone-like mineral matrix that simulates the bone formation: this environment is necessary osteoblast attachment and M A N U S C R I P T A C C E P T E D ACCEPTED MANUSCRIPT may drive osteogenic differentiation [15,16]. Various techniques, including magnetron sputtering, plasma spray methods, and physical vapor deposition, can be used to place a thin coat of HA on Ti materials [17][18][19][20]. However, achieving a uniform thin layer of HA on a complicated structure such as a tissue-engineering scaffold is challenging using these methods.…”

Relative Contributions of Surface Roughness and Crystalline Structure to the Biocompatibility of Titanium Nitride and Titanium Oxide Coatings Deposited by PVD and TPS Coatings

“…It supplies the coating material in the form of atoms, molecules, or ions that are generated from a target and transports them to the substrate surface, on which condensation and reaction with atoms of the surface lattice take place [44]. PVD has the advantage over other existing coating methods of being a reproducible process for depositing thin, stable, durable, and uniform coatings effectively masking the underlying surface chemistry without altering the surface topography [45]. Cell adhesion to the implant surfaces represents the initial interaction, and it is influenced by the surface chemical and topographical characteristics.…”