Background: An accurate adaptation of the crown to the finish line is essential to minimize cement dissolution and to preserve periodontium in fixed partial denture cases. An accurate adaptation of crown is possible only when preparation details are captured adequately in the impression and transferred to cast. For these reasons, gingival displacement is necessary to capture subgingival preparation details.The aim of the present study is to measure in vivo the horizontal displacement of the gingival sulcus obtained by using three new cordless retraction materials (Magic Foam Cord®, Racegel and Astringent Retraction Paste) in comparison to medicated retraction cord. Materials and method: Thirty-two patients requiring porcelain fused to me
... Show MoreGeotechnical engineers have always been concerned with the stabilization of slopes. For this purpose,
various methods such as retaining walls, piles, and geosynthetics may be used to increase the safety factor of slopes prone to failure. The application of stone columns may also be another potential alternative for slope stabilization. Such columns have normally been used for cohesive soil improvement. Most slope analysis and design is based on deterministic approach i.e a set of single valued design parameter are adopted and a set of single valued factor of safety (FOS) is determined. Usually the FOS is selected in view of the understanding and knowledge of the material parameters, the problem geometry, the method of analysis and the
This study was chosen because of the entry of our regions into the seismic zone recently, where Diyala governorate was hit by the Halabja earthquake in 2017 by 7.3Mw. Therefore, the impact of earthquakes will be studied on the AL-Mafraq bridge foundations piles located in Iraq- east of Baghdad in Diyala Governorate and the extent of its resistance to the Halabjah, EL-Centro, and Kobe earthquakes with acceleration 0.1g, 0.34g, and 0.58g respectively. After modeling and performing the analysis by using Midas Gts-Nx software, the settlement (mm) results at nine nodes (four nodes for the pile cap and five nodes for the piles) were obtained for each of Halabjah, EL-Centro, and Kobe earthquakes to know the resistance of the br
... Show MoreThe research aims to build a list of digital citizenship axes and standards and indicators emanating from them, which should be included in the content of the computer textbook scheduled for second grade intermediate students in Iraq, and the analysis of the above mentioned book according to the same list using the descriptive analytical method ((method of content analysis)). The research community and its sample consisted of the content of the computer textbook scheduled for the second year intermediate students for the academic year 2018-2019, and the research tool was built in its initial form after reference to a set of specialized literature and previous studies that dealt with topics related to digital citizenship, and the authenticit
... Show MoreIn this study, composite materials consisting of Activated Carbon (AC) and Zeolite were prepared for application in the removal of methylene blue and lead from an aqueous solution. The optimum synthesis method involves the use of metakaolinization and zeolitization, in the presence of activated carbon from kaolin, to form Zeolite. First, Kaolin was thermally activated into amorphous kaolin (metakaolinization); then the resultant metakaolin was attacked by alkaline, transforming it into crystalline zeolite (zeolitization). Using nitrogen adsorption and SEM techniques, the examination and characterization of composite materials confirmed the presence of a homogenous distribution of Zeolite throughout the activated carbon.
... Show MoreRepresent the current study and tagged (the credibility of digital image and its reflection on the process of cognitive picture releases) scientific effort is designed to detect realizing press releases and the extent affected the credibility of the digital image by selecting the relationship between digital photo and the extent of their credibility on the one hand and between the process of cognition and Press Photo of the hand Other than the consequent establishment researcher collects materials to serve the scientific research topic in three chaptersCombine the first one methodological framework for the search of the research problem and its significance and the desired objective be achieved together with the definition of the most im
... Show MoreBackground: Dental caries is one of the most significant problems in world health care. Restoring carious primary teeth is one of the major treatment goals for Children, and the light activated resin restoration materials like composite, resin-modified glass ionomer and polyacid-modified which was introduced in dentistry in 1970, widely used in clinical dentistry but its application increased dramatically in recent years because of its biocompatibility, color matching, good adhesive properties of its resemblance in physical and mechanical aspects to tooth. The aim of this study: To evaluate the microleakage of Polyacid-Modified Composite resin Compared to Flowable Hybrid Composite and Resin-Modified Glass ionomer cement. Materials and me
... Show MoreThe present study focused mainly on the vibration analysis of composite laminated plates subjected to
thermal and mechanical loads or without any load (free vibration). Natural frequency and dynamic
response are analyzed by analytical, numerical and experimental analysis (by using impact hammer) for
different cases. The experimental investigation is to manufacture the laminates and to find mechanical
and thermal properties of glass-polyester such as longitudinal, transverse young modulus, shear modulus,
longitudinal and transverse thermal expansion and thermal conductivity. The vibration test carried to
find the three natural frequencies of plate. The design parameters of the laminates such as aspect ratio,
thickness
A cantilever beam is made from composite material which is consist of (matrix: polyester) and (particles: Silicon-Carbide) with different volume fraction of particles. A force is applied at the free end of beam with different values. The experimental maximum deflection of beam which occurs at the point of the applied load is recorded. The deflection and slope of beam are analyzed by using FEM modeling. MATLAB paltform is built to assemble the equations, vector and matrix of FEM and solving the unknown variables (deflection and slope) at each node. Also ANSYS platform is used to modeling beam in finite element and solve the problem. The numerical methods are used to compare the results with the theoretical and experimental data. A good ag
... Show MoreBuckling analysis of composite laminates for critical thermal (uniform and linear) and mechanical loads is reported here. The objective of this work is to carry out theoretical investigation of buckling analysis of composite plates under thermomechanical loads, and experimental investigation under mechanical loads. The analytical investigation involved certain mathematical preliminaries, a study of equations of orthotropic elasticity for classical laminated plate theory (CLPT), higher order shear deformation plate theory (HSDT) , and numerical analysis (Finite element method), then the equation of motion are derived and solved using Navier method and Levy method for symmetric and anti-symmetric cross-ply and angle-ply laminated plates t
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