Some metal compounds, including arsenic, beryllium, cadmium, chromium and nickel have long been recognized as human and animal carcinogens, while for other as antimony, cobalt, lead and vanadium their carcinogenic action are probable or possible. Except chromium (VI), carcinogenic metals are only weak mutagens in mammalian cells and often inactive in bacterial assays. Since the mutagenicity in ...

Background and Aim: High chipping rates of the veneering porcelain in zirconia ce-ramic restorations have been reported in many clinical studies. However, information on the bonding behavior of veneering porcelain to zirconia and lithium disilicate frameworks is limited. The purpose of this study was to evaluate the bond-ing strength of porcelain veneering to zirconia, lithium disilicate, nicke...

The purpose of this study was to examine how Co-Cr-Mo dental alloy behaves in the solutions of different pH value and different composition over a relatively long period of time. Co-Cr-Mo dental alloy was exposed in vitro to either simulated saliva (phosphate buffer pH 6.0), a highly acidic medium resembling the extreme conditions in the oral cavity (phosphate buffer pH 3.5), and in lactic acid...

AIM The aim of this study was to evaluate the effect of recasting base metal alloy on the metal-ceramic bond strength. MATERIALS AND METHODS A total of 60 test samples were prepared from new and recast nickel-chromium alloy and divided into six groups. In group A0, test samples were prepared from 100% new alloy. Groups A1, A2, A3, A4, and A5 were prepared from 50% new alloy and 50% casting re...

PURPOSE To compare the debonding/crack initiation strength (D/CIS) of a low-fusing pressable leucite-based glass ceramic (PC) fused to metal to a feldspathic porcelain (FP) fused to metal. MATERIALS & METHODS As per ISO 9693:1999, 40 rectangular metal specimens (25.0 mm x 0.5 mm x 3.0 mm) were prepared. Twenty of the specimens were cast in a base metal nickel-chromium alloy (BA), and 20 were ...

In this study we examined the hypothesis based on relevant literature survey that the in vitro corrosion behavior of a Cobalt-chrome dental casting alloy for metal-ceramic restorations is better than that of a Nickel-chrome dental casting alloy. The corrosion released metal ions were analysed by Inductively Coupled Plasma-Atomic Emission Spectroscopy. Moreover, the specimens were electrochemica...

The H-point standard addition method (HPSAM), based on spectrophotometric measurements for simultaneous determination of beryllium and aluminium, is described. This method is based on the difference between their rates of reactions with Chrome Azurol S (CAS) in cetyltrimethylammonium bromide (CTAB) micellar media. The results showed that beryllium and aluminium could be determined simultaneousl...

Beryl (Be3Al2Si6O18) is a beryllium ring silicate that is composed of six-membered rings of [SiO4]4-tetrahedral and it crystallizes in the hexagonal crystal system with P6/mcc symmetry [1]. Of these, beryl variety a chromium-bearing variety of beryl, otherwise called as Emerald (Be3Al2Si6O18:Cr) contains vanadium, beryllium, iron, chromium. The refractive index, density and hardness of Emerald ...

BACKGROUND The Toxics Exposure Assessment Columbia-Harvard (TEACH) project assessed exposures and cancer risks from urban air pollutants in a population of high school teenagers in New York City (NYC) and Los Angeles (LA). Forty-six high school students participated in NYC and 41 in LA, most in two seasons in 1999 and 2000, respectively. METHODS Personal, indoor home, and outdoor home 48-hr s...