It is found that hypersensitive teeth have a larger number and wider patent tubules than those of non-sensitive teeth. Objective: The aim of this study is to compare between the effects of diode laser at different power densities, with and without sodium fluoride on the sealing of exposed dentinal tubules and dentin permeability. Materials and methods: 118 teeth were used. Samples were divided into three major groups. The first consisted of 100 teeth used for permeability test. The second consisted of 16 teeth for measuring external surface temperature elevation while irradiation. The third, in turn, consisted of one pair of teeth observed under SEM for dentine surface morphology analysis. Results: For dentin permeability measurement, the results revealed a highly significant difference between the control group and 2, 3 W with varnish groups. For the external surface temperature elevation, the results revealed that temperature rise, for both laser alone and with varnish groups, was between (67-97.9 ∘C) at 1.6, 2 W. SEM analysis revealed that approximately optimum sealing of tubules occurred in 2W with the varnish group. Conclusions: The combined application of 940 nm diode laser at 2W with 809.7 W/cm² power densities, with sodium fluoride white varnish show a significant improvement in their effects on dentin permeability reduction as compared to each treatment alone.
four coordinated complexes for divalent metal ions : Mn, Fe, Co, Ni, Cu and Cd have been synthesized using bidentate Schiff base ligand type (NN)formed by the condensation of o-phenylenediamine , p- methylbenzadehyde and furfural in methanol. The ligand was reacted with divalent metal chloride forming complexes of the types :[M(L)Cl2] where : MII=Mn, Fe, Ni, Cu, and Cd . These new compounds were characterized by elemental analysis, spectroscopic methods (FT-IR, U.V-Vis, 1HNMR (for ligand only and atomic absorption) , magnetic susceptibility, chloride content along with conductivity measurement. These studies revealed that the geometry for all complexes about central metal ion is tetrahedral.
The present work included study of the effects of weather conditions such as solar radiation and ambient temperature on solar panels (monocrystalline 30 Watts) via proposed mathematical model, MATLAB_Simulation was used by scripts file to create a special code to solve the mathematical model , The latter is single –diode model (Five parameter) ,Where the effect of ambient temperature and solar radiation on the output of the solar panel was studied, the Newton Raphson method was used to find the output current of the solar panel and plot P-V ,I-V curves, the performance of the PV was determined at Standard Test Condition (STC) (1000W/m2)and a comparison between theoretical and experimental results were done .The best efficiency
... Show MoreTo investigate and assess the effects of land use and land cover (LULC) on concentrations of heavy metals in the surface soils of Lesser Zab River Basin (LZRB), 25 surface soil samples were taken from different LULC classes. Heavy metals concentrations were measured and their enrichment factors were calculated. Most of the LZRB soil samples are moderately alkaline with pH>8 and characterized by low organic content. The average abundance of the major oxides follow the decreasing order of SiO2 % > CaO % > Al2O3 % > Fe2O3 %> MgO > K2O % > TiO2 % > Na2O % > SO3 % > P2O5 %. A correlation matrix revealed that clay and feldspar minerals, Fe and Mn oxides / hydroxides are the most important carrier phase for several
... Show MoreThe aim of this work is oriented to increase film cooling effectiveness value through numerical investigations for flow of Mach number not more than 0.3 around vane surface, to find the effects of inclination and compounds angles of round holes in staggered rows on adiabatic film cooling effectiveness of vane suction side. Multi cylindrical film cooling hole cases were studied with pitch ratio P/d =2 and 3, local blowing ratios M=0.382, 0.77 and 1.14, inclination angles a=30° and 45°, compound angles β= 0°, 15°, 30° and 45° and local momentum ratios I= 0.084, 0.34 and 0.756 for better cooling process.
A numerica
... Show MoreBackground: Cataract is a major cause of visual impairment and blindness around the world. This study evaluated the in vitro antioxidant and anti-cataract activities of Cnidoscolus aconitifolius leaves extract and fractions. Antioxidant activities were evaluated by 2,2-diphenyl-1-picrylhydrazyl (DPPH), 2,2-azinobis (3-ethylbenzothiozoline-6-sulfonic acid) (ABTS), total reducing power, and hydrogen peroxide scavenging assays. Anti-cataract potential was evaluated in vitro using goat lenses divided into eight groups of different treatments and incubated in artificial aqueous humor at 37 °C for 72 hours. Glucose-induced opacity in the lenses was observed and biochemical indices quantified (cata
... Show MoreBackground: Nickel-titanium (NiTi) archwires have become increasingly popular because of their ability to release constant light forces, which are especially useful during initial alignment and leveling phase. The aim of the present study was to investigate and compare the load–deflection characteristics of four commercially available NiTi archwires. Materials and methods: 200 NiTi 0.014, 0.016, 0.018, 0.016x0.022 and 0.019x0.025-inch nickel–titanium archwires from four different manufacturers (3M, Ortho Technology, Jiscop and Astar) were tested. The load-deflection properties of these archwires were evaluated by a full arch bending test in both palatal and gingival directionsat 37°C temperature using a universal material t
... Show MoreLeishmania are protozoan parasites belonging to the family Trypanosomatidae that cause high morbidity and mortality levels with a wide spectrum of clinical syndrome. This study aimed to investigate the effect of liposomal amphotericine B (AmBisome) drug on promastigote and axenic amastigote stages of Leishmania donovani isolate (MHOM/IQ/2005/MRU15)in comparison with pentostam SbV drug. Different concentrations of AmBisome and SbV drugs were investigated against Leishmania donovani promastigote and axenic amastigote. The ICR50R values of SbV and AmBisome drugs on promastigote were10.12 mg/ml and 2.21μg/ml, respectively, while they were 0.77μg/ml for axenic amastigote for both drugs. The present study concluded that axenic amastigote was
... Show MoreLeishmania are protozoan parasites belonging to the family Trypanosomatidae that cause high morbidity and mortality levels with a wide spectrum of clinical syndrome. This study aimed to investigate the effect of liposomal amphotericin B (AmBisome) drug on promastigote and axenic amastigote stages of Leishmania tropica. From the 20 isolates of cutaneous leishmaniasis collected from patients attended to the AL-Karama Teaching Hospital in Baghdad during the period from October 2013 until February 2014, only three isolates successfully transformed to motile promastigote stage in the culture media. The most active one is included in this study. Different concentrations of liposomal amphotericin B (AmBisome) and pentostam Sb (V) drugs were inv
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