Alumina toughened zirconia (ATZ) and zirconia toughened alumina (ZTA) are currently the materials of choice to meet the need for tough, strong, and bioinert ceramics for medical devices. However, the mechanical properties of ZrO2/Al2O3 dispersion ceramics could be considerably increased by reducing the corresponding grain sizes and by improving the homogeneity of the phase dispersion. Here, we ...

The corrosion behavior of three sorts of refractories based on alumina-graphite were studied by immersion tests. The melts included smelting reduction molten slag and corresponding carbon saturated molten iron. The influence of test temperature, FeO content in slag and specimen rotative velocity on the corrosion rate of refractories was examined. By means of SEM and EDS, the microstructure chan...

Currently, titanium or specific titanium alloys are the most often used materials for the fabrication of dental implants. Many studies have confirmed the osseointegrative capacity and clinical long-term performance of moderately rough titanium implants. However, disadvantages have also been reported with regard to peri-implant infections and the titanium metal properties. Tooth colored ceramic ...

AIM The aim of this systematic review was to screen the literature in order to locate animal and clinical data on bone-implant contact (BIC) and clinical survival/success that would help to answer the question 'Are ceramic implants a viable alternative to titanium implants?' MATERIAL AND METHODS A literature search was performed in the following databases: (1) the Cochrane Oral Health Group's...

Alumina-Mullite-Zirconia ceramic composites were prepared by reaction sintering of alumina, zircon mixture and the sintering aids of magnesia and titania at temperatures of 1400 and 1600 C for 2 hours. The development of different phases and microstructures of the composites were analysed to assess the relative influence of the additives on the formation of alumina-zirconia-mullite compos...

This report presents the results obtained by the five U.S. participating laboratories in the Versailles Advanced Materials and Standards (VAMAS) round-robin for fracture toughness of advanced ceramics. Three test methods were used: indentation fracture, indentation strength, and single-edge pre-cracked beam. Two materials were tested: a gas-pressure sintered silicon nitride and a zirconia tough...

Objectives: The aim of this prospective cohort study was to compute the long-term clinical survival and complication rates of alumina-toughened zirconia abutments used for implant-supported restorations and to evaluate the effects of several clinical variables on these rates. Material and methods: From May 1998 to September 2010, 213 patients aged 18 years or older were recruited. The patients ...

The isothermal isotopic exchange reaction of O2 with 16O of chromium(VI) oxide supported on zirconia, alumina, and titania has been investigated with in situ laser Raman spectroscopy. The isotopic exchange reaction is dependent on the support type, the Cr loading, and the reaction temperature. Complete isotopic exchange of chromium(VI) oxide with O2 is difficult to achieve and requires several ...

The aim of this in vitro study was to evaluate the effect of silica and aluminosilicate nanocomposite coating of zirconia-based dental ceramic by a sol-gel dip-coating technique on the bond strength of veneering porcelain to the yttria-stabilized tetragonal zirconia polycrystal (Y-TZP) in vitro. Thirty Y-TZP blocks (10 mm ×10 mm ×3 mm) were prepared and were assigned to four experimental groups...

The purpose of this study was to evaluate the biomechanical and histological behavior of a ceria-stabilized zirconia-alumina nanocomposite (NanoZr) in comparison with that of 3 mol% yttria-stabilized tetragonal zirconia polycrystalline (3Y-TZP) in Sprague Dawley rats. Cylindrical NanoZr and 3Y-TZP implants (diameter 1 mm, length 2 mm) were used. Implant-surface morphology and surface roughness ...