N. Bahremandi Tolou, M. H. Fathi, A. Monshi, V. S. Mortazavi,f. Shirani, M. Mohammadi,
Volume 10, Issue 2 (6-2013)
Abstract
Abstract:In recent years, there have been many attempts to improve the properties of dental amalgam. The aim of the present investigation was fabrication and characterization of dental amalgams containing TiO2 nanoparticles and evaluation of their compressive strength, antibacterial and corrosion behavior. In this experimental research, TiO2 nanoparticles (TiO2 NPs) were added to reference amalgam alloy powder and then, dental amalgam was prepared. In order to investigate the effect of TiO2 NPs on properties of dental amalgam, 0, 0.5, 1, 2 and 3 wt. % of TiO2 NPs were added to amalgam alloy powder and the prepared composite powder was triturated by a given percent of mercury. Xray diffraction (XRD), Scanning Electron Microscopy (SEM) and Energy-Dispersive Spectroscopy (EDS) techniques were used to characterize the prepared specimens. Potentiodynamic polarization corrosion tests were performed in the Normal Saline (0.9 wt. % NaCl) Solutions as electrolytes at 37°C. The results showed that the corrosion behavior of the dental amalgam with 0.5 or 1 wt. % TiO2 NPs is similar to the corrosion behavior of the reference amalgam, while with increasing the weight percent of TiO2 NPs, the corrosion rate increases. Also, the results of this investigation indicated that adding TiO2 NPs in amounts of up to 1 wt. % to amalgam alloy powder improve compressive strength of dental amalgam and has no destructive influence on its corrosion behavior. As well as, according to antibacterial results, TiO2 NPs can increase the biocompatibility and antibacterial activity of dental amalgam. The results of present study suggest that amalgam/ TiO2 NPs nanocomposite with 1% of TiO2 NPs could be regarded as a biocompatible and bioactive dental material that provide better characters for dental applications.
M. S. Mahmoudi Jozee, S. Sanjabi, O. Mirzaee,
Volume 13, Issue 3 (9-2016)
Abstract
A homogenous TiO2 / multi-walled carbon nanotubes(MWCNTs) composite film were prepared by electrophoretic co-deposition from organic suspension on a stainless steel substrate. In this study, MWCNTs was incorporated to the coating because of their long structure and their capability to be functionalized by different inorganic groups on the surface. FTIR spectroscopy showed the existence of carboxylic groups on the modified carbon nanotubes surface. The effect of applied electrical fields, deposition time and concentration of nanoparticulates on coatings morphology were investigated by scanning electron microscopy. It was found that combination of MWCNTs within TiO2 matrix eliminating micro cracks presented on TiO2 coating. Also, by increasing the deposition voltages, micro cracks were increased. SEM observation of the coatings revealed that TiO2/multi-walled carbon nanotubes coatings produced from optimized electric field was uniform and had good adhesive to the substrate.
