Back ground: During acrylic resin processing, the mold must be separated from the surface of the gypsum to prevent liquid resin from penetrating into the gypsum, and water from the gypsum seeping into the acrylic resin. For many years, tin foil was the most acceptable separating medium, and because it's difficult to apply, a tin-foil substitute is used. In this study, olive oil is used as an alternative to tin foil separating medium for first time, so the aim of the study was to evaluate its effect as a separating medium on some physical properties such as (surface roughness, water sorption and solubility) of acrylic resins denture base comparing it with those processed using tin-foil and tin foil substitute such as (cold mold seal) separating medium. Materials and methods: One hundred forty two acrylic resins samples (124) were prepared falling in two main groups: [heat and cold-cured acrylic denture base resins ], for each group three types of separating medium were used and five tests (10 samples) for each test were carried out , and (4) samples for the chemical composition. Result: From the result obtained, tin foil is one of the most satisfactory separating media in getting the best properties when using it as a separating medium, while, a statistically no-significant difference have been noticed between olive oil and cold-mold seal samples concerning physical and mechanical properties of tested groups. Infrared spectroscopy analysis showed that, no changes were found in the chemical composition of both heat and cold-cured acrylic resins denture base after using olive oil as a separating medium. Conclusion: Lastly, from the results of this study it may be concluded, that olive oil may be used as a substitute for tin foil and cold – mold seal separating medium in processing both heat and cold – cure acrylic resin denture base.
Atheists have spread in the modern era, so that atheism has become a bad phenomenon in the world in general and in Islamic societies in particular, so the research aims to study the individual and social effects left by atheism on the atheists themselves, and the research included multiple axes: atheism linguistically and idiomatically, atheism in the Qur’an Noble and Modern (and Contemporary) Atheism Statistics: and the reasons for atheism: Studying the phenomenon of atheism in Iraq as a model, then studying the effects of atheism: on the individual first, then atheism and its impact on society, then the conclusion, recommendations, sources and references
ABSTRACT. A new three metal complexes of La(III), Ce(IV) and UO2(II) ions have been synthesized based on a Schiff base derived from the condensation of L-histidine and anisaldehyde. All prepared compounds were characterized by different spectroscopic techniques and Density-functional theory (DFT) calculations. The complexes were proposed to have an octahedral structure based on the investigated results. The optimized shape, numbering system, and dipole moment vector of Ligand and La, Ce, and UO2 (1:1) chelates were investigated. The Schiff base ligand and complexes exhibit moderate action against all of the bacteria tested, with P. aeruginosa, Klebsiella sp., and E. faecalis respectively being the order of inhibition.
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Background: This study was formulated to compare the effect of 5%hydrofluoric acid in comparison to 37%phosphoric acid with and without the application of silane on bond strength of composite to porcelain. Materials and Methods: Specimen preparation was divided in to two phases, metal-disks fabrication (8mm-diameter and 4mm-thickness) and ceramic veneering. Thirty two specimens were prepared, sandblasted with 50 μm aluminum oxide, and divided into four groups of eight samples. Groups I and III were etched with 37%phosphoric acid while groups II and IV were etched with 5%hydrofluoric acid; and groups I and II were silaneted while groups III and IV were not. Heliobond, and resin composite were applied to each specimen using a plastic transpa
... Show MoreBackground: Many types of instruments and techniques are used in the instrumentation of the root canal system. These instruments and techniques may extrude debris beyond the apical foramen and may cause post-instrumentation complications. The aim of this study was to evaluate the amount of apically extruded debris resulted by using 4 types of nickel-titanium instruments (WaveOne, TRUShape 3D conforming files, Hyflex CM, and One Shape files) during endodontic instrumentation. Materials and methods: Forty freshly extracted human mandibular second premolar with straight canals and a single apex were collected for this study. All teeth were cut to similar lengths. Pre-weighted glass vials were used as collecting containers. Samples were randoml
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Background: The long term survival of dental implants is evaluated by the amount of crestal bone loss around the implants. Some initial loss of bone around dental implants is generally expected. There is reason to believe that reflecting a mucoperiosteal flap promotes crestal bone loss in the initial phase after an implant has been inserted. The surgical placement of a dental implant fixture is constantly changing and in recent years, there has been some interest in developing techniques that minimize the invasive nature of the procedure, with flapless implant surgery being advocated. The purpose of this study was to compare the radiographic level of the peri- implant bone after implant placement between traditional flapped surgery and f
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The research aims to identify the effect of the training program that is based on integrating futuristic thinking skills with classroom interaction patterns on mathematics teachers in order to provide their students with creative solution skills. The research sample consisted of 31teachers (15 teachers for the experimental group and 16 for the control groups). The researcher developed a measure for the academic self-efficacy consisting of (39) items. Its validity, reliability, coefficient of difficulty and discriminatory power were estimated. To analyze the findings, the researcher adopted the Mann-Whitney (U) test and the effect size, and the findings were as follows: There is a statistically significant difference at the significance leve
... Show MoreSchools and artistic trends derive their themes from artistic styles and styles as methods followed by the artist to express his themes embodied in the values of artistic and plastic elements as symbols and signs that can be described according to the type of art school and the extent to which the artist is influenced in employing them as a goal to achieve the plastic achievement in the painting, and from those vocabulary (human beings nature Life) as encoded messages that have an appearance and an interior, the appearance of which are forms, colors, formats and distributions of space and their interior meanings and semantics embody attitudes, events and circumstances that stem from the social depth and daily life and derive their comp
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حصاة الحالب واعراضها تؤثر على حياة المريض بصوره سلبيه، عدة علاجات متوفرة لعلاج حصاة الحالب من ضمنها مراقبه المريض، استخدام ادويه تفتيت الحصاة، استخدام موجات الفوق الصوتية تفتيت الحصاة بناظور الحالب، استخراج الحصاة جراحيا او بالناظور البطني, استخدام ناظور الحالب وتفتيت الحصاة بالليزر هي الطريقة المفضلة لعلاج حصاة اسفل الحالب. الهدف من الدراسة:لمقارنه تأثير ومضاعفات استخدام تقنيه الطحن او تقنيه التكسي
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