Inflammatory Response to Cobalt-Chromium Alloys Fabricated With Different Techniques

Abstract

Objectives: To explore the in vitro cytokine expression of human peripheral blood mononuclear cells exposed to cobaltchromium alloys, manufactured with different techniques, in comparison with commercially pure titanium grade 4 and titanium alloy grade 23. Material and Methods: Peripheral blood mononuclear cells (PBMC) were collected from 10 healthy blood donors and exposed to machine-ground coin-shaped: (a) cobalt-chromium (Co-Cr) specimens (n = 5) manufactured by four techniques, i.e. cast, milled, laser melted and presintered milled; (b) commercially pure titanium grade 4; and (c) titanium alloy grade 23. The cells were cultured for 4, 24 and 72 hours followed by investigations of pro-and anti-inflammatory cytokine release using Bio-Plex Pro™. Results: In general, the PBMC produced significantly more cytokines when exposed to the cast and presintered milled Co-Cr materials compared to laser melted, milled Co-Cr and titanium materials. Conclusions: Within the limitation of the present study, it may be suggested that cast and presintered milled cobalt-chromium alloys provoke a stronger inflammatory response compared to milled and laser melted cobalt-chromium alloys and titanium materials.

Thermal expansion and corrosion resistance of cobalt-chromium alloys fabricated by contemporary manufacturing processes. An in vitro study

“…The influence of the manufacturing technique on the mechanical properties, ion release, toxicity of released elements and surface roughness has been considered in recent studies on cobalt chromium. [19][20][21][22][23] However, the parameters like corrosion resistance and thermal expansion though important in the long-term survival of restorations have not been considered till now. Hence, the present study was planned to assess the thermal expansion and corrosion resistance of Co-Cr alloy fabricated using DMLS and MIL and compared these with the conventional casting alloy.…”

A review on manufacturing processes of cobalt‐chromium alloy implants and its impact on corrosion resistance and biocompatibility

“…Kassapidou et al141 investigated the cytotoxicity of CoCr alloys prepared by casting, milling, laser sintering, and pre-sintered milling.None of the alloys used in the study were cytotoxic when tested per the ISO 10993-5 standard. However, when the same research group investigated cytokine expression of human peripheral blood mononuclear cells, the cast and pre-sintered milled CoCr alloy samples showed a stronger inflammatory response when compared to other samples 171. On exposure to cast CoCr alloy specimens, the following was observed: (a) a significantly higher level of pro-inflammatory cytokines (IL-1β, IL-6, IL-8, IL-17, IFN-γ, and TNF-α) when compared to milled CoCr, laser melted CoCr, cp-Ti and Ti-6Al-4 V specimens; (b) a higher level of anti-inflammatory cytokines (IL-4) when compared to milled CoCr and laser melted CoCr; (c) a higher level of antiinflammatory cytokines (IL-4, IL-10, IL-12, IL-RA) when compared to cp-Ti.…”