objective: this experimental in vitro study compared marginal adaptation of indirect composite, glass-ceramic inlays and direct composite. materials and methods: seventy-five recently extracted human molars were randomly divided into three groups (n=25) and mesio-occluso-distal cavities with the same dimensions were prepared in the teeth. indirect composite and glass-ceramic inlays were fabrica...

Glasses in the system 24.5Na2O.24.5CaO.6P2O5.xSrO.(45-x)SiO2 have been studied composition region of x = 0–15 mol%. The as-prepared glasses are transparent and an amorphous network structure. On other hand, heat-treated transformed to opaque white glass-ceramic characterized by their highly crystalline Crystalline apatite (calcium phosphate, Ca3(PO4)2), wollastonite silicate, CaSiO3), strontium...

Complex sequential crystallization mechanisms were investigated in the glass composition 70GeO2-10Na2O-20Ta2O5 prepared by melt-quenching. In a first stage, classical volume-nucleated of sodium tantalate perovskite Na2Ta8O21 is induced under short time heat-treatments whereas longer annealing treatments promote formation surface spherical structures known as spherulites. These singular glass-ce...

in this paper, zno thin film is deposited on slide glass substrate using the sol-gel process. presenting well-defined orientation of zno thin films nanostructure were obtained by dip coating of zinc acetate dihydrate, monoethanolamine (mea), de-ionized water and isopropanol alcohol. the annealed zno thin films were transparent ca 85-90% in visible range with an absorption edges at about 375 nm....

Fractures during clinical function have been reported as the major concern associated with all-ceramic dental restorations. The aim of this study was to analyze the fracture features of glass-ceramic and zirconia-based restorations fractured during clinical use. Twenty-seven crowns and onlays were supplied by dentists and dental technicians with information about type of cement and time in func...

The aim of this in vitro study was to observe the effect of hydrofluoric acid (HF) on the surface of two glass ceramics for Cerec and to compare it with the effect on a conventional glass ceramic. Discs were cut from a feldspathic ceramic block (VitaMKII) and from a leucite reinforced glass ceramic (IPS EMPRESS CAD) for Cerec. 5% and 9% HF concentrations were used during 1 min and 2 min each. A...

Synthetic vitreous fibers are inorganic fibrous materials, manufactured principally from glass, rock, minerals, slag, and processed inorganic oxides. Synthetic vitreous fibers are manufactured by several processes, all of which involve cooling of a stream of high-temperature, molten inorganic oxides. Commercially important synthetic vitreous fibers are primarily silica-based, but contain variou...

Both titanium and ceramic materials provide specific advantages in dental implant technology. However, some problems, like hypersensitivity reactions, corrosion and mechanical failure, have been reported. Therefore, the combining of both materials to take advantage of their pros, while eliminating their respective cons, would be desirable. Hence, we introduced a new technique to bond titanium a...

This paper describes the system packaging of the processor cage for the IBM eServer z900. This server contains the world’s most complex multichip module (MCM), with a wiring length of 1 km and a maximum power of 1300 W on a glass-ceramic substrate. The z900 MCM contains 35 chips comprising the heart of the central electronic complex (CEC) of this server. This MCM was implemented using two diffe...