Effects of gold coating on experimental implant fixation

Abstract

Insertions of orthopedic implants are traumatic procedures that trigger an inflammatory response. Macrophages have been shown to liberate gold ions from metallic gold. Gold ions are known to act in an antiinflammatory manner by inhibiting cellular NF-κB–DNA binding and suppressing I-κ B-kinase activation. The present study investigated whether gilding implant surfaces augmented early implant osseointegration and implant fixation by its modulatory effect on the local inflammatory response. Ion release was traced by autometallographic silver enhancement. Gold-coated cylindrical porous coated Ti6Al4V implants were inserted press-fit in the proximal part of tibiae in nine canines and control implants without gold inserted contralateral. Observation time was 4 weeks. Biomechanical push-out tests showed that implants with gold coating had ~50% decrease in mechanical strength and stiffness. Histomorphometrical analyses showed gold-coated implants had a decrease in overall total bone-to-implant contact of 35%. Autometallographic analysis revealed few cells loaded with gold close to the gilded implant surface. The findings demonstrate that gilding of implants negatively affects mechanical strength and osseointegration because of a significant effect of the released gold ions on the local inflammatory process around the implant. The possibility that a partial metallic gold coating could prolong the period of satisfactory mechanical strength, however, cannot be excluded.

Effects of titania nanotubes with or without bovine serum albumin loaded on human gingival fibroblasts

“…Numerous studies [2][3][4][5] have demonstrated that osseointegration is facilitated by surface modifications. Over time, the surface designs of the endosseous and transmucosal areas have dynamically changed to enable faster integration after implantation and improve long-term bone maintenance; long-term bone maintenance relies heavily on the surface modification of the transmucosal area because the surface positively affects the three functions of the implants: the attachment of soft tissue, 6,7 the inhibition of bacterial biofilm adhesion, 8,9 and the preservation of the crestal bone.…”

Assessment of modified gold surfaced titanium implants on skeletal fixation

“…Observation time of four weeks was used in this study, as previous studies have been able to show relevant differences within four weeks with the same model 6. With the same four week observation time, a significant difference was found in our former study with the comparison of complete gold‐coated implants with control titanium‐alloy implants (reduced fixation with press‐fit implant with full gold coating) 15. Of note, a longer observation time may result in a measurable difference but may also show a general increase in new bone on both surfaces.…”

“…Thomsen et al considered gold as a noble metal that does not create surface oxides, and thus does not affect the surrounding tissue, whilst titanium surfaces were active oxidized surfaces. Although metallic gold is not active, we reckon that it interacts with the surrounding tissue due to the organism's always‐active inflammatory cells, such as macrophages, and their dissolucytosis of implant surfaces, as illustrated by Danscher11 and the previous pure gold study 15. However, gold's effect is not on cell growth or cell differentiation, and the reduced bone formation is not considered to be due to any toxicity or biocompatibility issues.…”

“…Previously, we compared pure gold coated experimental implants with control titanium‐alloy implants in a related press fit implant model and found both a reduction in new bone formation and inferior mechanical stability. These findings were presumably due to an inhibited periimplant remodeling around the press fit implant 15. The present study introduces a new coating that combines gold and titanium as a surface substrate and evaluates it in a gap implant model.…”

The effect of electrical stimulation on the differentiation of hESCs adhered onto fibronectin-coated gold nanoparticles

“…In biomedical fields, conductive gold films have been reported to enhance the proliferation and differentiation of adhered cells such as nerve and endothelial cells [8][9][10]. Thus, gold-coated surfaces have suitable biocompatibility, which indicates that they have the potential for biomedical applications [11][12][13].…”