Selective etching of injection molded zirconia-toughened alumina: Towards osseointegrated and antibacterial ceramic implants

Abstract

Due to their outstanding mechanical properties and excellent biocompatibility, zirconiatoughened alumina (ZTA) ceramics have become the gold standard in orthopedics for the fabrication of ceramic bearing components over the last decade. However, ZTA is bioinert, which hampers its implantation in direct contact with bone. Furthermore, periprosthetic joint infections are now the leading cause of failure for joint arthroplasty prostheses. To address both issues, an improved surface design is required: a controlled micro-and nano-roughness can promote osseointegration and limit bacterial adhesion whereas surface porosity allows loading and delivery of antibacterial compounds. In this work, we developed an integrated strategy aiming to provide both osseointegrative and antibacterial properties to ZTA surfaces. The microtopography was controlled by injection molding. Meanwhile a novel process involving the selective dissolution of zirconia (selective etching) was used to produce nano-roughness and interconnected nanoporosity. Potential utilization of the porosity for loading and delivery of antibiotic molecules was demonstrated, and the impact of selective etching on mechanical properties and hydrothermal stability was shown to be limited. The combination of injection molding and selective etching thus appears promising for fabricating a new generation of ZTA components implantable in direct contact with bone.3

Inorganic nanohybrids combat antibiotic-resistant bacteria hiding within human macrophages

“…24,25 Lipid and polymer-based capsules have been investigated for their function as carriers, where the core of the nanoparticle serves as a vehicle to carry active molecules. 26 Fascinating results have been achieved in a study using antibiotic-loaded liposomes for the delivery of vancomycin to Kupffer cells containing S. aureus by harnessing their intrinsic ability to catch foreign particles. 13 In this way, vancomycin could be delivered to the previously inaccessible intracellular reservoir.…”

The In Vitro Bioactivity, Degradation, and Cytotoxicity of Polymer-Derived Wollastonite-Diopside Glass-Ceramics

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Instrumented Indentation of Super-Insulating Silica Compacts

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