Background: The bond strength of root canal sealers to dentin and gutta-percha seems to be an important property for maintaining the stability of root canal filling, which potentially influences both leakage and root strength. The objective of this, in vitro, study was to evaluate the shear bond strength of three different endodontic sealers (Gutta-Flow, AH Plus, Apexit Plus) to dentin, in the presence and absence of the smear layer and gutta percha. Material and Methods: After slicing off the occlusal 2mm of 60 extracted human maxillary premolar teeth, the exposed dentin served as the tested surfaces; the teeth were fixed with cold cure acrylic, and were divided into two groups according to the smear layer presence, group A without smear layer, when dentin surfaces were irrigated with EDTA 17% followed by distilled water then subdivided into 3 subgroups according to the type of sealer used; group B when dentin surfaces were washed with distilled water only, then subdivided into 3 subgroups. Thirty samples of gutta-percha were prepared and named as group C which was subdivided into 3 subgroups. Five mm long section of polyethylene tubes were placed on the dentin or gutta percha surfaces and filled with freshly mixed sealer. After one week, all the samples were tested for shear bond strength by the Instron Universal Testing Machine at a cross head speed of 0.5 mm/min. The data was calculated in MPa and was statistically analyzed Result: There was a highly significant difference in the shear bond strength (P < 0.05) in comparison among the tested groups, GuttaFlow showed non-significant difference in bond strength to dentin with and without smear layer, while AH Plus and Apexit Plus showed a high significant difference. Conclusions: AHPlus showed the highest shear bond strength in all the tested samples, while GuttaFlow was the least. Additionally, AH Plus and Apexit Plus shear bond strengths were affected by the smear layer removal, while GuttaFlow was not.
Background: Tooth wear is one of the most common problems in the older dentate population which results from the interaction of three processes (attrition, abrasion and erosion) and it affects all societies, different age groups, and all cultures. This study was achieved to evaluate the prevalence and distribution of tooth wear among institutionalized residents in Baghdad city\ Iraq. Subjects and Methods: This survey was accomplished on four private and one governmental institution in Baghdad city. One-hundred twenty three (61 males, 62 females) aged 50-89 years were participated in this study. The diagnosis and recording of tooth wear were according to criteria of Smith and Knight. Results: The prevalence of tooth wear was 100% with a mean
... Show MoreOrganizations adopt a number of procedures and instructions in their field of activities in order to aid their resources development and energies to serve their entrepreneurial orientations. This calls for preparing a range of mechanisms to mitigate the strictness and complexity of procedures. The ambiguity and severe complexity of procedures means acknowledging the loss in energy and this in turn impedes the hopes while in the same time weakens the enthusiasm in these organizations and an impedes the possibility to achieve continues innovation, thereby losing opportunities to the level of surrender to the risks and assuming them to be unconquered obstacles.
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The aim of this research is to introduce agricultural insurance, to define financing in the form of salam and the role of agricultural insurance in the prevention of risks to agricultural finance operations in the form of salam by verifying the hypotheses through which to reach the results, including the imposition of risks for agricultural finance in the form of salam, The study of agricultural finance in the form of salm, the deductive approach to the development of the problem of research and hypotheses, and the inductive method to extrapolate the results through analysis and brother The researcher concluded that agricultural insurance works to bridge the risks facing agricultural finance in the form of the ladder in cases of
... Show MoreThe current study was conducted to evaluate the effect a mixture of threespecies of arbuscular mycorrhizal fungi (Glomus etunicatum, G. leptotichum andRhizophagus intraradices) double and triple mixture and organic matter by usingplastic pots in the greenhouse at some mycorrhiza and physiological limitationscharacteristics in tomato plant after four and eight weeks of cultivation. Theresults of the determinants mycorrhiza significant increase the percentage ofmycorrhizal frequency F% dry weight of roots mycorrhiza (g.plant-1) andorganic matter in all mycorrhiza single, double and triple mixture after four andeight weeks cultivation treatments. The highest percentage of mycorrhizalfrequency and increase the dry weight of the root in the trea
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The provision of openings in serviceable reinforced concrete beams may result in a substantial decline in the beam's capacity and integrity, indicating the necessity of opening strengthening. The present study investigates the experimental response of reinforced concrete T-beams with multiple web-strengthened openings disposed in shear span to static and impact loads. Fourteen RC T-beams were tested in two groups, each of seven beams. The first group was tested under static loading up to failure, while the second group was tested under repeated impact loading until the width of shear cracks reached 0.3 mm. The residual static strengths of the beams subjected to impact loading were then determined. The test variables considered were
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The provision of openings in serviceable reinforced concrete beams may result in a substantial decline in the beam's capacity and integrity, indicating the necessity of opening strengthening. The present study investigates the experimental response of reinforced concrete T-beams with multiple web-strengthened openings disposed in shear span to static and impact loads. Fourteen RC T-beams were tested in two groups, each of seven beams. The first group was tested under static loading up to failure, while the second group was tested under repeated impact loading until the width of shear cracks reached 0.3 mm. The residual static strengths of the beams subjected to impact loading were then determined. The test variables considered were
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Abstract:
The phenomenon of financial failure is one of the phenomena that requires special attention and in-depth study due to its significant impact on various parties, whether they are internal or external and those who benefit from financial performance reports. With the increase in cases of bankruptcy and default facing companies and banks, interest has increased in understanding the reasons that led to this financial failure. This growing interest should be a reason to develop models and analytical methods that help in the early detection of this increasing phenomenon in recent year . The research examines the use of
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