High density sodium lithium niobate lead free ceramics near the morphtropic phase boundary [NaxLi1−xNbO3, (LNN), x=0.12] were prepared by the solid state reaction method. XRD patterns showed that the lattice structures were changed after polarization. The temperature dependence of the dielectric constant and dielectric loss, pyroelectric coefficient and DSC curves of LNN ceramics showed that th...

Background: This study sought to assess the effect of glazing and polishing surface treatments on the optical behavior of zirconia-reinforced lithium silicate ceramics thermocycled in different solutions. Methods:Computer-aided design/computer-aided manufacturing ceramics (VITA Suprinity) were cut into samples (n=104) measuring 1.5x14x10 mm according to t...

The effect of the addition of V2O5 on the structure, sintering and dielectric properties of M-phase (Li1+xyNb1-x-3yTix+4y)O3 ceramics has been investigated. Homogeneous substitution of V5+ for Nb5+ was obtained in LiNb0.6(1-x) V0.6xTi0.5O3 for x ≤ 0.02. The addition of V2O5 led to a large reduction in the sintering temperature and samples with x = 0.02 could be fully densified at 900oC. The sub...

IR-transparent chalcogenide glass-ceramics were fabricated through a careful ceramization process of the as-prepared 65GeS2 25Ga2S3 10LiI glasses at a temperature of 403 1C for various durations. Owing to the precipitation of LixGaySz crystals with a Ga2S3-like structure, clear second-harmonic generation was observed in the sample crystallized at 403 1C for 60 h, which has a greatly improved re...

We report two cases of surface deterioration of a zirconia ceramic femoral head associated with phase transformation after total hip arthroplasty. One head was retrieved at revision due to recurrent dislocation after six years and the other because of failure of the locking mechanism of the polyethylene liner after three years. The monoclinic content of the zirconia ceramics rose from 1% to abo...

The mechanical properties of porous ceramics are greatly influenced by their microstructure. Therefore, mechanical behavior of highly porous ceramics is different from that of dense ceramics. In this work, we evaluate different mechanical testing methods such as static compression, Brazilian disc test and 3-point bending on their suitability for comparison of highly porous ceramic materials. It...

The lifetime of a ceramic is dependent on the presence of incidental cracks and their gradual propagation under the conditions of the oral cavity. The objective of this study was to examine the long-term strength of glass-infiltrated alumina- and various zirconia ceramics currently used in CAD/CAM systems to manufacture crown and bridge frameworks. Fracture mechanics were applied to determine c...

The demand for metal free ceramics with highly biocompatible dental restorative material has increased during the past decade. The esthetic demands made on dental restorations has resulted in an increased use of dental ceramics. For meeting the requirements of dental materials with improved strength and toughness, various new ceramic materials as well as new techniques have been developed durin...

The biaxial flexural strength and cyclic fatigue biaxial flexural strength of CAD/CAM ceramics polished with #220, 400, 600 and 1000 diamond pads were measured in an effort to determine the effect of surface roughness on fatigue behavior of dental ceramics. The surface roughness was improved after polishing with a smaller diamond grain pad. The flexural strengths of the specimens polished with ...

Biomaterials can be endowed with biologically instructive properties by changing basic parameters such as elasticity and surface texture. However, translation from in vitro proof of concept to clinical application is largely missing. Porous calcium phosphate ceramics are used to treat small bone defects but in general do not induce stem cell differentiation, which is essential for regenerating ...