Background: The bond strength of the root canal sealers to dentin seems to be a very important property for maintaining the integrity and the seal of root canal filling. The aim of this study was to evaluate the shear bond strength of four different obturation systems using push-out test. Materials and methods: Forty straight palatal roots of the maxillary first molars teeth were used in this study, these roots were instrumented using crown down technique and ProTaper system, instrumentation were done with copious irrigation of 2.5% sodium hypochlorite and 17% buffered solution of EDTA was used as final irrigant followed by distilled water, roots were randomly divided into four groups according to the obturation system (ten teeth for each group): Group I: AH26 sealer and lateral condensation technique, Group II: AH26 sealer and single cone obturation technique, Group III: AH26 sealer and thermafil obturation technique and Group IV: RealSeal SE sealer and lateral condensation technique, the roots then stored in moist environment at 37°C for one week The roots were embedded in clear acrylic resin and each root sectioned into three levels apical, middle and cervical. The measurement of each section was taken to prepare the supporting jig for the sections and the punch used in pushout test, the bond strength was measured using computerized universal testing machine each section fixed in the machine so that the load applied from apical to cervical direction at 0.5mm/min. speed and the computer drew curve to show the higher bond force before dislodgment of the filling material. These forces were divided by the surface area to obtain the bond strength in MPa. Results: Statistical analysis was performed and the result showed avery highly significant differences between the four obturation systems at each level and there were non significant differences between all level apical, middle and cervical within each obturation system except a significant difference found between cervical and apical level in single cone obturation system. Conclusion: This study showed that the shear bond strength of AH26 sealer was higher than RealSeal SE sealer when the same obturation technique was used. The shear bond strength was affected by the obturation technique and lateral condensation technique showed higher bond strength than thermafil and single cone obturation technique when the same type of sealer was used and the bond strength was not or little affected by the tooth level
This research was conducted to study the histological structure of the eye in the tree frog (Hyla arborea savignyi) and showed that it is composed of the eyeball and the lens and optic nerve. Appeared eyeball is surrounded by three Tunica from the inside to the outside are Tunica Interna, Tunica vasculosa, Tunica fibrosa. The tunica interna consists of the retina that consists of 10 layers are from outer to inner pigment epithelial layer, rods and cones layer, external limiting membrane, outer nuclear layer, outer plexiform layer, inner nuclear layer, inner plexiform layer , ganglion cells layer , nerve fibers layer, internal limiting membrane .The vascular tunic or Uvea consists of the choroid, ciliary body , and iris . The fibrous coat co
... Show MoreToxoplasmosis is the term for infection and disease in man and animal caused by a parasite called Toxoplasma gondii. The more susceptible to infect with toxoplasmosis is the Diabetic patients, due to low level of immunity response. The aim of current study is to investigate the immune status of diabetes mellitus type 2. One hundred and seventy five samples of both diabetes mellitus type 2patients and controls which had been tested by ELISA technique to detect anti-Toxoplasma Abs (IgG and IgM). The positive toxoplasmosis samples were tested to detect the level of TNF alpha and MIG. Results for all samples clarified that seronegative for IgM antibodies while 53 (53%) diabetic patients were seropositive for IgG antibodies and for toxoplasmosis
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In most of Beckett’s plays , there are prominent elements of absurdity that are landmarks of his style and the way of his writing like : the physical and the spiritual decay of characters, the disintegration of language as it becomes no longer a means of human communication because there is an inability to establish any kind of mental contact among them. These elements are quite apparent in Beckett’s “All That Fall”. The play exhibits a list of conflicts: one is between powerful forces as that between the force of life represented by Maddy and the forces of death represented by Dan .The second is the conflict and contempt between the old generation and the new one in the case of Dan’s desire to kill the boy fetching
... Show MoreThe financial market plays an important role in influencing the economic sectors, including the private industrial sector, through the provision of capital and transfer from savers to investors for the purpose of establishing or expanding projects. Therefore, the financial market is one of the important tools in stimulating the economy in general and the industrial sector in particular, Through the inclusion of industrial companies in the financial market and the introduction of industrial shares to the public, and then provide the necessary funding to stimulate the private industrial sector, Iraq is one of the oil-dependent countries on the oil sector mainly, which lacks industrial production, which is from Are the sectors that
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The kestrel Falco tinnunculus specimens coIldeted in Iraq are found infected with one or more species of the following helminthes; Physaloptera alata (Nematoda), Cladataenia globifera (Cestoda), Prosthogonimus cuneatus (Trernatoda), and Sphaeriorostris sp. (Acanthocephala) with a total infection rate of 30.56%. The results are compared and discussed with the pertinent literature.
Theoretical trends have appeared Which posed the concept of biological structures in contemporary architecture concept, Spread through the emergence of architectural production that reflect and indicate the nature of the construction structures based on the ideas and principles of biological structures in biological science: Despite the emergence of many architectural proposals that tried to explain the concept in the field of architecture, but it is not dealt with in depth and not given a comprehensive definition: So there was need to search for the concept and its beginning in the biological field as a general framework down to the field of architecture for the purpose of reducing the limits of their search framework T
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With the advancement of technology ,the study of cross-cultural communication via on line has become an important and researchable topic in linguistic theory and its applications.The aims of this study are two- fold (a) exploring the influence of cultural diversity on on-line interaction between American native speakers (NSs) and Iraqi non-native speakers (NNSs) of English which, together with other factors might potentially lead to what Thomas(1983) calls "pragmatic failure" (PF), a main cause of communication breakdowns and (b) specifying which type of PF occurs more frequently between the two groups along with the reasons behind such failures. To achie
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Perhaps it is of paramount importance for researchers to present grammatical topics with a uniqueness that distinguishes them from everything else that may overlap with them, and a specificity that distances them from much of what may be thought to be similar to them or similar to them. The subject pronoun is one of these topics that should be considered. Due to the uniqueness of this pronoun among the rest of the family of pronouns, with features and adverbs that deserve research and study, and then analysis and treatment; Because of its scientific value, it goes hand in hand with other pronouns. This topic would not have drawn my attention or received much of it had it not raised some fundamental questions, including, f
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