Enhanced osteogenic activity of titania-modified zirconia implant by ultraviolet irradiation

Abstract

Zirconia is a superior implant material owing to its high mechanical strength, durable corrosion resistance, superior aesthetic effect and excellent biocompatibility. However, the bioactivity of zirconia surfaces remains a great challenge for implant osseointegration. A titania (TiO2) coating was innovatively synthesized on the surface of zirconia by infiltration in a suspension of zirconium oxychloride and titania for dense sintering. Subsequently, the coating was subjected to ultraviolet (UV) light to enhance the biological inertness of zirconia. Scanning electron microscopy (SEM), X-ray photoelectron spectroscopy (XPS), X-ray diffraction (XRD) and contact angle analysis were conducted to confirm the surface characteristics. Afterwards, in vitro assessments of cell adhesion, proliferation and osteogenic differentiation of MC3T3-E1 cells were performed. Zirconia samples were implanted into rat femurs to assess biocompatibility and host tissue response in vivo. Micro-CT evaluation and histological testing were conducted. After UV irradiation, the content of hydroxyl groups and hydrophilicity of TiO2-modified zirconia were significantly increased. The results of in vitro experiments showed that TiO2-modified zirconia subjected to UV light could promote cell proliferation and spreading, enhance ALP activity and the degree of mineralization, and upregulate osteogenesis-related genes. Furthermore, in vivo assessments confirmed that UV-irradiated TiO2-modified zirconia implants maximized the promotion of osseointegration. TiO2-modified zirconia after UV treatment will have broad clinical application prospects in improving the osseointegration of zirconia implants.

Fabrication and evaluation of silver modified micro/nano structured titanium implant

“…It indicated that appropriate Ag + concentration provide an advantageous condition for osteogenic differentiation at an early stage, while the promotion was decreased at late stage. The reason was mainly attributed to the conversion from ALP to mineralization, which was also proved by previous studies [39][40][41]. In addition, the quantity of mineralization of cells after culturing for 14 d is lower than that for 7d, which was attributed to the sustained Ag + release and decreased cell viability for the next 7d.…”

“…The reason was mainly attributed to the conversion from ALP to mineralization, which was also proved by previous studies. [39][40][41] In addition, the quantity of mineralization of cells after culturing for 14 d is lower than that for 7d, which was attributed to the sustained Ag + release and decreased cell viability for the next 7d. Previous study reported that the introduce of Ag nanoparticles may had almost no influence on osteogenic differentiation on the first 3d, while the sustained silver ion release would have negative effect on mineralization after 7d.…”

In Vitro and In Vivo Studies of Hydrogenated Titanium Dioxide Nanotubes with Superhydrophilic Surfaces during Early Osseointegration

“…In another study, stable hydrophilicity was achieved by reactive plasma modification and wet storage, which led to improved cell adhesion, viability, and ALP activity [ 45 ]. Tang et al [ 46 ] used UV irradiation to greatly improve the hydrophilicity of the TiO 2 coating on zirconia implant, and in vitro assessments displayed the enhanced ALP activity, mineralization, and osteogenesis-related genes expression. In specific, the H-Nano group with superhydrophilic surfaces in this study displayed optimal cell attachment and cell functions, including ALP synthesis, ECM mineralization, and osteogenesis-related gene expression, compared to the M and Nano groups.…”

Biological properties of hydroxyapatite coatings on titanium dioxide nanotube surfaces using negative pressure method

“…As an important indicator of early osteogenic differentiation, alkaline phosphatase (ALP) activity was used to determine the osteogenic properties of the samples 21 . MC3T3‐E1 cells were seeded on the samples at a density of 2 × 10 4 cells/well and cultured for 4 and 7 days in the osteogenic induction medium (the basic culture medium with 100 nM dexamethasone, 50 μg/mL l ‐ascorbic acid and 10 mM β‐glycerol phosphate).…”