Particulate gold as an anti‐inflammatory mediator in bone allograft—An animal study

Abstract

Morselized allograft is widely used when increased bone stock is needed in implant surgery. Gold ions liberated from metallic gold surfaces act in an anti-inflammatory manner by inhibiting cellular NF-κB-DNA binding and suppressing I-κ B-kinase activation. This study investigated the effect of 45-63 μm sized gold particles mixed in morselized allograft. It was hypothesized that bio-released gold ions would influence allograft reabsorption, increase mechanical stability, and further stimulate osseointegration. A pair of 10 mm long implants surrounded by a 2.5-mm gap was inserted in proximal part of each humerus in 10 sheep. Each gap was filled with morselized allograft with 1.29 mg gold particles or nothing. Observation time was 12 weeks. The gold ion liberation was visualized by autometallographic tracing and showed liberation of gold ions. Biomechanical push-out tests and stereological histomorphometric analyses showed no statistically significant differences in the two groups. Although particulate gold was primarily observed surrounded by bone marrow tissue, no obvious clinically relevant short-term effects could be measured using gold as an anti-inflammatory mediator. These findings show that the released gold ions have only influenced cells adjacent to the particles without influencing the fixation and illustrates gold ions' limited field of effect. We suggest a new design for orthopedic implants by introducing gold dots on the prosthesis surface. This aims at suppressing the inflammatory foci along the implant-bone zone and reduces the risk of chronic inflammation before aseptic loosening without affecting bone remodeling. This implant model will be investigated in further studies.

Incorporating gold into nanocrystalline silver dressings reduces grain boundary size and maintains suitable antimicrobial properties

“…Similarly to silver, gold and gold complexes have also been extensively used in medicine (7) and both their antimicrobial and anti‐inflammatory properties have been shown (8–10). For example, DC magnetron sputtering deposition of gold has resulted in fabric coatings that are antimicrobial (11).…”

Characterisation of Electroplated Gold Coatings for Dental Applications: Estimation of Thickness Using Non-Destructive Electron-Probe Microanalysis Related to Plating Time

“…Au coating these alternative alloys may reduce associated corrosion. The anti-inflammatory reaction of Au has long been recognised in the medical field [20][21][22][23]. If the physiological and physical benefits of gold can be maintained in thin coatings and the pathological effects of alternate materials, suitable for these modern fabrication techniques, can be shielded by the gold coatings, this would be a significant development in ensuring that the benefits of implant dentistry are available to a broad range of "patients" and not just those in a very high socio-economic bracket.…”

Iron–Gold Composites for Biodegradable Implants: In Vitro Investigation on Biodegradation and Biomineralization

“…Similarly, Au sputtering on the Fe surface also improved the degradation rate of Fe during the initial stage of immersion in simulated body fluids . Adding Au nanomaterials to the surface of the implant can lower the likelihood of chronic inflammation preceding aseptic loosening without compromising bone regeneration. , It is reported that though the surface-level metallurgical modifications might increase the material degradation rate during the initial implantation period through galvanic coupling, the degradation rate cannot be sustained due to the lack of these noble phases in the bulk of the material. , Huang et al , studied the incorporation of noble metallic elements such as Pt, Pd, Ag, and Au in relatively higher concentrations (from 2 to 5 wt %) and reported an increase in the degrading rate of Fe. Though the incorporation of noble metals to the Fe matrix enhances the degradation, toxicity due to the higher concentration of noble metals is to be considered .…”

“…34 Adding Au nanomaterials to the surface of the implant can lower the likelihood of chronic inflammation preceding aseptic loosening without compromising bone regeneration. 35,36 It is reported that though the surface-level metallurgical modifications might increase the material degradation rate during the initial implantation period through galvanic coupling, the degradation rate cannot be sustained due to the lack of these noble phases in the bulk of the material. 32,37 Huang et al 38,39 studied the incorporation of noble metallic elements such as Pt, Pd, Ag, and Au in relatively higher concentrations (from 2 to 5 wt %) and reported an increase in the degrading rate of Fe.…”