No abstract

In this paper, hydroxyapatite-carbon nanotube/titania (HA-CNT/TiO2) double layer coatings were successfully developed on titanium (Ti) substrates intended for biomedical applications. A TiO2 coating was firstly developed by anodization to improve bonding between HA and Ti, and then the layer of HA and CNTs was coated on the surface by the sol-gel process to improve the biocompatibility and mechanical properties of Ti. The surfaces of double layer coatings were uniform and crack-free with a thickness of about 7 μm. The bonding strength of the HA-CNT/TiO2 coating was higher than that of the pure HA and HA-CNT coatings. Additionally, in vitro cell experiments showed that CNTs promoted the adhesion of preosteoblasts on the HA-CNT/TiO2 double layer coatings. These unique surfaces combined with the osteoconductive properties of HA exhibited the excellent mechanical properties of CNTs. Therefore, the developed HA-CNT/TiO2 coatings on Ti substrates might be a promising material for bone replacement.

No abstract

No abstract

This study evaluated the influence of polydopamine treatment on the surface properties and bond strength of yttria‐stabilised tetragonal zirconia polycrystal (Y‐TZP). Sixty‐three zirconia blocks (10 × 10 × 2 mm) were randomly divided into three groups defined by surface treatment: (i) control group (C), (ii) grit‐blasted with 110 μm alumina particles (GB), and (iii) polydopamine (PDA) coating. The surfaces of specimens subjected to different treatments were investigated by X‐ray photoelectron spectroscopy (XPS), scanning electron microscopy (SEM), and water contact angle measurements. After the surface treatments, the specimens were cemented to resin composite cylinders. After bonding, the shear bond strength of the ceramic to the resin was measured, and the failure mode of each specimen was analysed using a stereomicroscope. The results indicated that the shear bond strength is highest for the GB treatment and lowest for the controls. However, the difference between groups GB and PDA was not statistically significant. In the control group, adhesive failure was predominant, whereas in the treatment groups, mixed mode failure was predominant. The pre‐treatment of Y‐TZP ceramic with the polydopamine coating might improve the bond strength of the resin cement to the zirconia ceramic.