The Sierra Nevada’s biological distinction and diversity are almost as legendary as its spectacular peaks and beautiful granite landscapes. The Sierra Nevada is recognized as a zoogeographic region on the basis of the coincidence of species ranges (for example, Udvardy 1969, 1975; Welsh 1994). Udvardy (1969) defined the Sierra Nevada bioregion as bounded by the Great Basin to the north and east...

to investigate and compare the amount of fluoride release of conventional, resin modified and nanofilled resin modified glass ionomer cements.tablets of glass-ionomer cements were immersed in deionized water and incubated at 37°c. after 1, 2, 7, 15 and 30 days, fluoride ion was measured under normal atmospheric conditions by fluoride ion selective electrode. buffer (tisab ii) was used to decomp...

objective: the aim of this study was to investigate the translucency of resin-modified glass-ionomer cements (rmgic) and polyacid-modified composite resin (pcmr) over a period of one year. materials and methods: the study was done on three rmgic (fuji ii lc, photac-fil aplicap and vitremer) and one pcmr (dyract). a conventional gic (fuji cap ii) and two composite resins (tetric and z 100) were ...

background: the clinical success of sandwich technique depends on the strength of resin-modified glass ionomer cement (rmgic) bonding to both dentin and resin composite. therefore, the shear bond strength (sbs) of resin composite bonded to rmgic utilizing different resin adhesives versus a gic-based adhesive was compared. materials and methods: in this in vitro study, 84 holes (5×2 mm) were pre...

 Oxyfluoride glass ceramics containing CaF2nano-crystals doped with Y3+ ions were prepared by one-step crystallization of SiO2- Al2O3- CaO- CaF2 glasses at different temperatures. X- ray diffraction (XRD) results have revealed that CaF2 was the only precipitated crystalline phase in glass ceramic samples. According to the XRD results, a glass ceramic was selected as the best sample in order to ...