Abstract: An unfavorable complication of root canal is vertical root fracture. The aim of present study is to evaluate the vertical root fracture of treated teeth filled with gutta percha and Resilon obturating material using different sealers. Forty mandibular premolars used in the study. Canals randomly divided into four groups (n=10). Group-A eugenol-based (Endofill) sealer with gutta percha; GroupB epoxy-amine (AH Plus) sealer with gutta percha; Group-C resin-based (Real Seal) sealer with Resilon; or Group-D epoxide-based (Perma Evolution) sealer with gutta percha. Roots mounted vertically in cold cure acrylic blocks and subjected to vertical loading with a crosshead speed of 1mm ̸min. The point at which fracture of the roots occurred recorded in Newton. Roots obturated with gutta percha and epoxide sealer show the highest resistance to vertical fracture (p<0.05). While, roots obturated with gutta percha and eugenol sealer revealed the lowest vertical fracture resistance value compare to other groups
Thermomechanical analysis (TMA) and differential scanning calorimetry (DSC) are used to investigate the effect of molding and annealing of polyester on the behavior of thermal expansion and crystallization since these factors play role in the reprocessing or recycling of the polymer. The dynamic mode of the TMA provides enhanced characterization information about the polyester since it separates the transitions into reversible and irreversible signals, and also reveals the progress of the amorphous regions as the polyester loses strength with the increasing temperature approaching melting. Slow cooling after annealing brings crystallization that may be attributed to molecular chain straightening due to orientation.
The research includes synthesis and identification of novel three amino acids ligands complexes of some heavy metal (II) ions by using the amino acids like glycine, L-alanine and L-valine. New metal mixed ligand complexes with amino acids are prepared the reaction by reacting the three amino acids with the metals(II) chloride by using 50% ethanolic solution and 50% distall water in the molar ratio [1:1:1:1] ( M:Gly:Ala:Val) except for Co(II) and Ni(II) complexes were found after diagnosis the coordination with both Lalanine and L-valine. The prepared complexes identified by using physical properties, flame atomic absorption and conductivity measurements, in addition, mass, FT.IR and UV.vis spectrum as well magnetic moment data. The general
... Show MoreProtection of the oil pipelineswhich extracted from the wells was found to shut the well and prevent the leakage of oil when broken using safety valve. This valve is automatically activated by loss of pressure between the well and pipelines, which take the pressure, signal from hydraulic pressure sensor through pressure control valve which has constant or variable value but it is regulated manually. The manual regulatory process requires the presence of monitoring workers continuously near the wells which are always found in remote areas. In this paper, a smart system has been proposed that work with proportional pressure control valve and also electronic pressure sensor through Arduino controller, which is programmed in a way that satisfie
... Show MoreIn this work, composite materials were prepared by mixing different concentrations of ferrites with polyacrylonitrile (PAN) polymer. Using the electrospinning technique, these composites were deposited on a p-type silicon wafer. The prepared samples demonstrated nanofibers in both pure PAN polymers and their composites with ferrite. Prior to examining the humidity sensing effectiveness with a percentage of relative humidity at a frequency of 10 kHz, based on ambient temperature and a relative humidity range of 50–100%, the composite nanofibers demonstrated stronger humidity sensing compared to the pure PAN nanofibers, which demonstrated a powerful resistance response. More precisely, the PAN@ferrite nanocomposite showed a broad adsorption
... Show MoreIn this study, synthesis of polymer Nanocomposites through the blending of prepared polymers with polyvinyl alcohol (a synthetic polymer) or chitosan (a natural polymer) then mixed with nano oxide silica by many steps. The new compound [I] was obtained via reaction of 3,3’-dimethoxybiphenyl-4,4’-diamine as starting material with malic anhydride in DMF then treatment with ammonium persulfate (NH4 )2 S2 O8 (as the initiator) in order to produce polymer [II]. Also, we prepared new polymers [III-V] by using the same starting material (3,3’-dimethoxybiphenyl-4,4’-diamine) with glutaric acid or adipic acid or isophthalic acid in DMF and pyridine. In this study, new polymer blending [VI-IX] and [X-XIII] were synthesized from a prepared pol
... Show MorePseudomonas aeruginosa is a Gram-negative opportunistic pathogen and a model bacterium for studying virulence and bacterial social traits. While it can be isolated in low numbers from a wide variety of environments including soil and water, it can readily be found in almost any human/animal-impacted environment. It is a major cause of illness and death in humans with immunosuppressive and chronic conditions, and infections in these patients are difficult to treat due to a number of antibiotic resistance mechanisms and the organism’s propensity to form multicellular biofilms. One hundred twenty clinical samples and forty hospital environmental samples (various sources) were collected from hospitals in Baghdad city during the period from Oc
... Show MoreCollapse of the vapor bubble condensing in an immiscible is investigated for n-pentane and n-hexane vapors condensing in cold water and n-pentane in two different compositions of glycerin- water mixture. The rise velocity and the drag coefficient of the two-phase bubble are measured.
Background: Osteoporosis (OP) is a systemic disease characterized by low bone mass and micro architectural deterioration of bone tissue, resulting in an increased risk of fractures and has touched rampant proportions. Osteocalcin, one of the osteoblast-specific proteins, showed that its functions as a hormone improves glucose metabolism and reduces fat mass ratio. This study is aimed to estimate the osteocalcin and glucose level in blood serum of osteoporotic postmenopausal Women with and without Type 2 Diabetes.Materials and methods: 60 postmenopausal women with osteoporosis divided into two groups depending on with or without T2DM, 30 patients for each. Serum samples of 30 healthy postmenopausal women were collected as control group. Ost
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