Micro Shear Bond Strength between Glass Ionomer and Calcium Silicate Cements to Dentine: In Vitro Comparative Study

The research aims to evaluate the micro shear bond strength of the calcium silicate cement (Biodentine) and the glass ionomer cement (GIC) to dentine. The study was performed using upper or lower premolars, and samples were divided into six equal subgroups according to the time period (3 h, 1 day, 1 week, 2 weeks, 4 weeks, 8 weeks), in order to study changes in the values of shear bond strength with time. The comparative study showed that the success rate of adhesion in the Biodentine group was smaller than that in the GIC group for the tested premolars after 3 hours and one day, whereas the success rate in the Biodentine group was greater than that in the GIC group for the tested premolars after 8 weeks. Results showed a positive correlation between the mean values of shear bond strengths and the studied time in Biodentine group, which ranged from 1.49 ± 0.18 MPa at 3 hours to a maximum value of 2.65 ± 0.26 MPa after 8 weeks. While there was a negative correlation between the mean values and the studied time in the GIC group and values ranged from 3.02 ± 0.13 MPa at 3 hours and 2.06 ± 0.09 MPa at 8 weeks. The study showed the advantage of Biodentine compared with GIC in terms of micro-bonding to dentine, which can have a clinically significant importance in preventing the micro leakage and reducing bacterial contamination.

Critical Historical Reading of the Law of Unequal Historical Evolution

There are many views on the question of the logic and mechanisms of historical development of human society; visions and answers vary, to the extent of total conflict sometimes, on other issues that relate organically to the first question, perhaps the most prominent of which is the general picture of the historical evolution diagram, Sequentially spherical stages, as well as the question of the so-called nation or the multiple nations that alternately lead the ship of the evolution of human society in general. This is where the sharp contrast between the two theories of the so-called equal evolution and the unequal historical evolution as a problem from which the research begins and ends with emphasis on the credibility of the last thesis and on highlighting a large and dangerous part of the ideological manipulation and blindness of the first thesis. The latter, which is one of the moss serious thesis of European orientalism and the pervasive wooden understanding of the original thought of Marxist origin.

Capitalism Globalization and its Historical Stages (Critical analytical approach)

The research aims to solve one of the most complex issues of sociology of development and social change, not to mention the dismantling of one of the most important issues of sociology and sociology of culture. The issue of capitalist globalization and its historical stages of development, as well as the question of whether, especially at its new stage of development, it is a global system or global anarchy? Capitalism, by its structural logic, is not an antistatic system; it is a dynamic system open to shifting and shifting historical horizons. They have been deported at various stages, to a large extent, at the level of form or appearance, although they remain captive to content and one structural logic. As such, in the light of the recent results of the research, we have called for serious action to build a truly new world order based on the rules of pluralism, justice and democracy, as another system replacing the world order based on unilateralism, hegemony and dictatorship.

The effect of the self action potential energy of charge carrier located in isotropic layer on the energy gape in lead iodide layer

In this work, the effect of electric permittivity and thin layer thickness on the energy gape has been studied in a system consisting of three thin layers by means of finding the self action potential of charge carrier located in the central layer of this system. Then, the self action potential energy has been found by solving Schrödinger equation at the extracted potential. This study shows that energy gape of PbI2 decreases with layer thickness while it increases/decreases according to comparison between dielectric permittivity values of central layer and counterparts of two neighborhood layers on both sides.

Effect of EDTA and Naocl application on bond strength of Orthodontic Brackets with resin –modified glass ionomer (An in vitro study)

The Objective is to determined whether enamel conditioning with sodium hypochlorite (5,25%) and EDTA prior to etching was increased shear bond strength of orthodontic brackets bonded with resin – modified glass ionomer. our sample consisted of 42 extracted human premolars were randomly divided into 3 groups.

Study to compare shear bond strength of rebonded metal brackets which their bases are mechanically prepared.(In vitro study)

The aim of this study To compare in vitro shear bond strength (SBS) of different orthodontic adhesives in and rebonding metal brackets after preparing their bases mechanically. Material and methods:Sample consisted of 40 extracted first premolars, randomly divided into two groups (n=20),.Adhesive removed by tungsten carbide bur later the brackets were rebonded. The tests were performed in a tecnotest (6kN) SBS testing machine, at a speed of 1 mm/min. It was found that the mean shear bond strength of Reseliencewas 19.25 MPa and that of Heliosit orthodontic was 10.25MPa.We foundthat the mean shear bond strength of rebonding forReselience was 13.70 and 7.95 forHeliosit.The t-test revealed that there was a significant difference between the shear bond strength of the two groups. We found a significant difference between bonding and rebondingfor Reselience,while there was no significant difference between bonding and rebonding for Heliosit.

The effect of using belt truss and outriggers system on storey displacements and storey drifts in high-rise composite building

This research studies the use of outriggers and belt truss system for high-rise composite building subjected to earthquake load, consists of columns (W) and (HP), and beams (W), and central concrete core. Using (SAP2000) in three-dimensional (3D) analysis of building, storey displacements and storey drifts has been compared in four cases: 1. (MWBT): Model without belt truss and outriggers. 2. (MBT2): Model with two belt truss and outriggers at the levels (0.5H, H). 3. (MBT3): Model with three belt truss and outriggers at the levels (0.33H, 0.67H, H). 4. (MBT4): Model with four belt truss and outriggers at the levels (0.25H, 0.5H, 0.75H, H). Displacements reduction were 41.8%, 67.5%, 75.9%, respectively as compared to a model without any belt truss and outrigger system. So, using outrigger and belt truss system in high-rise buildings increase the stiffness and makes the structural form efficient under lateral load.

Imagination between the forces of the status of human cognition

The research is talking about the various self powers which human share with animal. And It sheds the light in particular on Imagination which mediates these power. It is the link between what before and after it. It restarts images of feelings and partial meanings which had been realized before, combines each other and separates other from another. Also, It greats new images which are not existed in outside world, and he Sense can,t realize them. Also, the research talks about powers of the mental realization which. specializes with Human Lonely and animal makes him distinguish of the res of .

Comparing the Bond Strength of two Ceramic Repair Systems to Zirconia Ceramic with and without Sandblasting. (An in-Vitro Study)

The Purpose of this study was to evaluate and compare the shear bond strength (SBS) of two composite repair systems to zirconia-ceramic with and without sandblasting.

The Effect of Surface Conditioning Methods on The Bond Strength of Zirconia to Resin Cement (in vitro)

This study aims to evaluate zirconia bond strength bonded with resin cement after deferent surface treatments.