Background: This study was aimed to investigate the effect of three lingual button (Nickel free / rectangular base, Nickel free / round base and Composite) and bonding environment, wet and dry enamel surface, on: the shear bond strength (SBS) of light and self-cured Resin Modified Glass Ionomer Cements, and the debonding failure sites. Materials and method: One hundred twenty no-carious, free of cracks maxillary first premolar teeth were selected. Three types of orthodontic lingual buttons were used in this study: Nickel free / rectangular base, Nickel free / round base and Composite buttons. The teeth were divided into two groups of sixty teeth each. One group was used for testing the chemically cured GC Fuji Ortho Resin modified Glass Ionomer (RMGIC), while the other was used for testing the light cured GC Fuji Ortho LC RMGIC. Each was further subdivided into two subgroup; thirty teeth were bonded to wet enamel surface while the other was bonded after drying the enamel surface. Then each ten teeth from each subgroup were bonded with only one type of buttons. The sample was tested for bond strength using the universal testing machine and the Adhesive Remnant Index (ARI) was inspected under the stereomicroscope. Results:The highest (SBS) values were obtained in the Nickel free / round base button with both types of RMGIC in wet and dry environment as revealed by ANOVA test. While t-test revealed that both systems of RMGIC yield relatively lower values of (SBS). Conclusions:The GC Fuji Ortho RMGICs resist shear force in dry better that in wet environment.Nickel free / round base buttons give the greatest shear bond strength among the three types of button.The composite buttons give greater bond strength in dry than in wet environment with both GC Fuji Ortho and GC Fuji Ortho LC RMGICs.
The objective of this research paper is two-fold. The first is a precise reading of the theoretical underpinnings of each of the strategic approaches: "Market approach" for (M. Porter), and the alternative resource-based approach (R B V), advocates for the idea that the two approaches are complementary. Secondly, we will discuss the possibility of combining the two competitive strategies: cost leadership and differentiation. Finally, we propose a consensual approach that we call "dual domination".
Background: Prematurity and its complications are the major causes of neonatal and infant morbidity and mortality. Although the cause of preterm labor is often unknown, numerous etiological risk factors may be implicated. To identify the risk factors that lead to prematurity and assess the neonatal outcomes that preterm neonates may develop. Methods: This case-control study was conducted at AL-Elwiya Pediatric Teaching Hospital, Baghdad, Iraq, from the 1st of June to the 31st of December 2019. A non-randomized sample of 700 neonates admitted to the neonatal care unit was included in this study and divided into two groups of preterm full-term neonates as the experimental and control groups, respectively (n=350 each). The same questionnaire w
... Show MoreIn the age of information and communication revolution, education as one of life
aspects has influenced with that revolution by integrating technology in education, which
have become as an important learning tools of the whole educational process . Technology,
when used appropriately, can help make science classroom a site of active learning and
critical thinking, furthering student inquiry and connections with different materials. It is
necessary to develop human rights education programs and materials for discretionary and
extracurricular activities as it provide them with the skills and tools so that they are
empowered to take action to realize their rights. Human rights education is a critical means of
instill
It is often needed in demographic research to modern statistical tools are flexible and convenient to keep up with the type of data available in Iraq in terms of the passage of the country far from periods of war and economic sanctions and instability of the security for a period of time . So, This research aims to propose the use of style nonparametric splines as a substitute for some of the compounds of analysis within the model Lee-Carter your appreciation rate for fertility detailed variable response in Iraq than the period (1977 - 2011) , and then predict for the period (2012-2031). This goal was achieved using a style nonparametric decomposition of singular value vehicles using the main deltoid , and then estimate the effect of time-s
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The aim of the present research is to identify the test wisdom and the preoccupation with learning and psychological tension among postgraduate students at the University of Samarra according to the variables of the department, gender, age, and employee or non-employee, and revealing the relationship between the test wisdom and the preoccupation with learning and psychological tension. The research sample consisted of (75) students randomly selected from postgraduate students at the college of Education. The researcher applies test –wisdom of (Mellman & Ebel) and measurement of preoccupation with learning prepared by (Al-zaabi 2013) also, the researcher used the scale of t
... Show MoreBumpiness in the atmosphere is the vertical movement of air, whether
upward or downward movement and the bumpiness is accompanied by areas
of unrest in the air and wind. And contribute to each of the coups thermal
fronts, wind, wind and thunderstorms. Moreover, bumpiness is net of the
reasons that lead to circumstances is appropriate to cut the wind, and this
contributes to the formation of bumpiness in the atmosphere. The study found
that the noon of the times, which is expected to occur where clear-air
bumpiness during flights because of the warmth of the earth's surface. The
study found increased incidence of air hole during the summer, especially
July, due to increased incidence of coup surface, while the s
Back ground: Oral lichen planus is a chronic inflammatory disease that affects the mucous membrane of the mouth. Several researchers suggest that oxidative stress is implicated in the pathogenesis of this disorder. It has been hypothesized that melatonin is powerful anti-oxidants and can easily cross the cell membrane and is considered a free radical scavenger of Hydroxid, Oxygen and Nitrogen dioxide, cortisol as a stress hormone and the immunoglobulin A as first line of defense and protection to the mucous membrane of the mouth are interrelated factors for the emergence of oral lichen planus. Aim of this study was to evaluate the level of melatonin, Cortisol and IgA in saliva of patients with oral lichen planus lesions in comparison with p
... Show MoreIn this paper, a polymer-based composite material was prepared by hand Lay-up method consisting of epoxy resin as a base material reinforced by magnesium oxide powder once and silicon dioxide powder again and with different weight ratios (3, 6, 9 and 12) wt %. The three-point bending test was performed in normal conditions and after immersion in sulfuric acid. The results showed that the bending value decreased with the increase of the weighted ratio of the reinforcement material (MgO, SiO2). The Bending of samples reinforced by SiO2 was found to be less than the bending of samples reinforced by particles (MgO). For example, the bending of the SiO2 sample (0.32 mm) at the weighted ratio (3%) and for the MgO (0.18mm) sample at the weight
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