Physical vapour deposition of zirconia on titanium: fabrication, characterization and interaction with human osteoblast cells

Advancements in incorporating metal ions onto the surface of biomedical titanium and its alloys via micro-arc oxidation: a research review

The incorporation of biologically active metallic elements into nano/micron-scale coatings through micro-arc oxidation (MAO) shows significant potential in enhancing the biological characteristics and functionality of titanium-based materials. By introducing diverse metal ions onto titanium implant surfaces, not only can their antibacterial, anti-inflammatory and corrosion resistance properties be heightened, but it also promotes vascular growth and facilitates the formation of new bone tissue. This review provides a thorough examination of recent advancements in this field, covering the characteristics of commonly used metal ions and their associated preparation parameters. It also highlights the diverse applications of specific metal ions in enhancing osteogenesis, angiogenesis, antibacterial efficacy, anti-inflammatory and corrosion resistance properties of titanium implants. Furthermore, the review discusses challenges faced and future prospects in this promising area of research. In conclusion, the synergistic approach of micro-arc oxidation and metal ion doping demonstrates substantial promise in advancing the effectiveness of biomedical titanium and its alloys, promising improved outcomes in medical implant applications.

Epithelial Biological Response to Machined Titanium vs. PVD Zirconium-Coated Titanium: An In Vitro Study

The aim of this study was to compare the epithelial biological response to machined titanium Ti-6Al-4V grade 5 and titanium Ti-6Al-4V grade 5 coated with zirconia (ZrN) by physical vapor deposition (PVD). Human keratinocytes were cultured in six-well plates. Machined titanium TiAl4V4 grade 5 (T1) and ZrN-coated titanium TiAl4V4 grade 5 (T2) discs were placed in two different wells. The remaining two wells served as control (C). Scanning electron microscopy (SEM) and energy-dispersive spectroscopy (EDS) were performed to compare the T1 and T2 surfaces. Subsequent analyses were performed to explore the effect of T1 and T2 contact with human keratinocyte HUKE cell lines. Cell viability was evaluated using a trypan blue exclusion test and MTT assay. Cell lysates from C, T1, and T2 were Western blotted to evaluate E-cadherin and Integrin-α6β4 expression. SEM revealed that T2 was smoother and more homogeneous than T1. EDS showed homogeneous and uniform distribution of ZrN coating on T2. Cell viability analyses did not show significant differences between T1 and T2. Furthermore, E-cadherin and Integrin-α6β4 expressions of the epithelial cells cultured in T1 and T2 were similar. Therefore, titanium Ti-6Al-4V grade 5 surfaces coated with ZrN by PVD seem to be similar substrates to the uncoated surfaces for keratinocyte adhesion and proliferation.

Interactions of Osteoprogenitor Cells with a Novel Zirconia Implant Surface

Background: This study compared the in vitro response of a mouse pre-osteoblast cell line on a novel sandblasted zirconia surface with that of titanium. Material and Methods: The MC3T3-E1 subclone 4 osteoblast precursor cell line was cultured on either sandblasted titanium (SBCpTi) or sandblasted zirconia (SBY-TZP). The surface topography was analysed by three-dimensional laser microscopy and scanning electron microscope. The wettability of the discs was also assessed. The cellular response was quantified by assessing the morphology (day 1), proliferation (day 1, 3, 5, 7, 9), viability (day 1, 9), and migration (0, 6, 24 h) assays. Results: The sandblasting surface treatment in both titanium and zirconia increased the surface roughness by rendering a defined surface topography with titanium showing more apparent nano-topography. The wettability of the two surfaces showed no significant difference. The zirconia surface resulted in improved cellular spreading and a significantly increased rate of migration compared to titanium. However, the cellular proliferation and viability noted in our experiments were not significantly different on the zirconia and titanium surfaces. Conclusions: The novel, roughened zirconia surface elicited cellular responses comparable to, or exceeding that, of titanium. Therefore, this novel zirconia surface may be an acceptable substitute for titanium as a dental implant material.

Effect of titanium implants with coatings of different pore sizes on adhesion and osteogenic differentiation of BMSCs

A variety of surface modification methods are applied to modify titanium implants to improve their biological activity. Micro-arc oxidation (MAO) can relatively simply and efficiently produce porous coatings with high bioactivity and bond strength on titanium surfaces. However, there is no conclusion about the effect of coatings with different pore sizes produced by MAO on bone marrow mesenchymal stem cells (BMSCs). To study the effect of different pore sizes on BMSCs, rat BMSCs were applied to detect the effect of different pore sizes prepared by MAO on cell adhesion and osteogenic differentiation. Three groups of coatings with different pore sizes were successfully prepared, and the pore size was within the range of 3-10 µm. Importantly, the expression of adhesion-related protein integrin β1 and osteogenic-related proteins OSX and ALP increased along with the increase in pore size. This study showed that the porous coating prepared by MAO promotes BMSCs adhesion and osteogenic differentiation. It reveals that the pore size is in the range of 3-10 µm and the larger pores are more beneficial for BMSCs adhesion and osteogenic differentiation. This study is instructive for optimizing the design of biomedical implant surfaces.