Background: Crown preparation of vital teeth involve the removal of a sound tooth structure, and when enamel removed this lead to exposed dentin with an increase in the number of open dentinal tubules also the diameter of dentinal tubules will increase, furthermore lead to increase movement of fluids inside the tubules all that causes post preparation sensitivity. The aim of this study is to evaluate the effect of desensitizing by Er:Cr:YSGG laser on shear bond strength of prepared tooth and resin cement. Materials and methods: Thirty sound maxillary premolars, grouped into three groups(n=10). Group A is the control group, group B irradiated by Er:Cr:YSGG laser with (0.25 W, 20 Hz, 10%water and air), group C irradiated by Er:Cr:YSGG laser with (0.5 W, 20 Hz, 10% water and air). Results: SEM examination showed complete occlusion of opened dentinal tubules after laser irradiation of both groups that irradiated with laser. Statistical analysis showed significant increase in surface roughness in group B and C. SBS was significantly increase in group B with no significant increase in group C. Conclusion: Er:Cr:YSGG laser can occlude open dentinal tubules without and adverse effect on the retention of the restoration, on the contrary it increase bonding strength. And this increasing was significant in group B with (0.25W, 20 Hz, 10 % water and air). suggestion: so the parameters used in group B (0.25 W, 20Hz, 10 % water and air) is recommended for desensitizing prepared tooth and induce enhancement to the bonding strength of resin to tooth surface.
The humid and warm conditions in greenhouses provide an excellent environment for pests’ living conditions, and therefore, they provide ideal medium for alien introductions. Molluscs are among the most significant pests that infest plastic covered greenhouses. To identify and report their mollusc species, 23 greenhouses in Iraq were surveyed between March 2023 and April 2024. Of these, 11 were found to be infested with snails. A total of 158 specimens were collected and morphologically identified to seven species: Monacha obstructa (L. Pfeiffer, 1842), Eobania vermiculata (O.F. Müller, 1774), Xeropicta krynickii (Krynicki, 1833), Rumina decollata (Linnaeus, 1758), Polygyra cereolus (Megerle Von Mühlfeld, 1818), Cochlicella barba
... Show MoreVitiligo is an acquired idiopathic skin disorder characterized by depigmented macules due to loss of cutaneous melanocytes. A potential role of the immune dysfunction has been suggested in vitiligo, so to test this hypothesis, certain cytokines (IL-17A and TNF-?) and immunoglobulins (IgM, IgG, IgA and total IgE) were investigated in all participants. The study included: 60 patients with age range between (6-55) year; 30(11 males and 19 females) were untreated and 30(12 males and 18 females) were treated with Narrow Band Ultraviolet-B (NB-UVB) and 30 (14 males and 16 females) apparently healthy control. Serum was separated and cytokines (IL-17A and TNF-?) and total immunoglobulin E (IgE) were detected by using Enzyme Linked Immunosorbent Ass
... Show MoreBack ground: Glass ionomer materials lack resistance to wear and pressure and are susceptible to moisture during the initial stages of setting and dehydration. So this study was done to assess diametral tensile strength and microhardness of glass ionomer reinforced by different amounts of hydroxyapatite. Materials and methods: In this study a hydroxyapatite material was added to glass monomer cement at different ratios: 10%, 15%, 20%, 25% and 30% (by weight). The diametral tensile strength test described by the British standard specification for zinc polycarboxylate cement was used in this study and the microhardness test was performed using Vickers microhardness testing machine and the microhardness values were calculated and statistical c
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This research aims at know the position of Al-Jassas Al- Hanafi (D. 370 AH) of "As-Sifat Al- Khbriya", through his interpretation: (the provisions of Qur'an), by studying his interpretation of the verses related to this issue.
The most significant results of this study that Al-Jassas did not consider the words that called: "As-Sifat Al- Khbriya" as adjectives to Allah almighty, but he consider them contained an inappropriate meaning to Allah almighty, thus it must be referred to the perfect arbitrator, so he was believe in opinion of interpretation. and interpretations of Al-Jassas for the related of the Qur'an verses relat
... Show MoreThis research is concerned with studying the representations of the event in the drawings of the ancient civilizations of the world, and the research consists of two axes, the axis of the theoretical framework, which included (the research problem, its aim, its limits, and the definition of its terminology).
The research aims to reveal how the event pattern was formulated by the artist on the surface of his visual achievement, and the limits of the search were spatial in the ancient civilizations of Iraq, Egypt, Greece and Rome, but the limits of the temporal research could not be determined because they were before birth, and objectively:
representations of the event in the civilizations of the ancient world This axis also in
research summary
Praise be to Allah، and prayers and peace be upon His Messenger and His chosen one، his family، companions and his family and his family.
After that، this is a study on the question of the claim، as one of the controversial questions that are the mainstay of debates، and I looked at it: the limit of the question of the claim، its importance، its impact، its aspects of corruption، its sections، and the representation of its sections of the fundamentalist controversy;
The research was according to the following plan:
Introduction، in which she mentioned: the importance of the research topic and the reason for its selection، its questions، its l
... Show MoreStylistics is the analysis of the language of literary texts integrated within various approaches to create a framework of different devices that describe and distinct a particular work. Therefore, feminist stylistics relied on theories of feminist criticism tries to present a counter- image of a woman both in language use and society, to draw attention , raise awareness and change ways that gender represents. Feminist stylistic analysis is related not only to describe sexism in a text, but also to analyze the way that point of view, agency, metaphor, and transitivity choices are unanticipatedly and carefully connected to issues of gender(Mills,1995:1) &nb
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Liquefied petroleum gas (LPG), Natural gas (NG) and hydrogen were used to operate spark ignition internal combustion engine Ricardo E6, to compare NOx emissions emitted from the engine, with that emitted from engine fueled with gasoline as a fuel.
The study was done when engine operated at HUCR for gasoline, compared with its operation at HUCR for each fuel. Compression ratio, equivalence ratio and spark timing were studied at constant speed 25rps.
The results appeared that NOx concentrations will be at maximum value in the lean side near the stoichiometric ratio, and reduced with moving away from this ratio for mixture at both s
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