Background: 37% phosphoric acid (PA) is the traditional enamel etching technique prior to bracket adhesion, yet it has been implicated in numerous enamel injuries. The purpose of the current study was to create a calcium phosphate (CaP) etching paste in a simplified capsule formula that can underpin clinically adequate bracket bond strength without jeopardizing the integrity of enamel upon the debracketing procedure. Materials and Methods: micro-sized hydroxyapatite (HA) powder was mixed with 40% PA solution to prepare experimental acidic CaP paste. Sixty human premolars were assigned into two groups of 30 each. Enamel conditioning was accomplished using 37% PA-gel for control group and CaP paste for experimental group. Each group was further divided into two subgroups regarding the water storage (WS) period (24 h and 30 days). Shear bond strength (SBS) test conducted with examination of debonded surfaces for adhesive remnants and enamel damage using a digital microscope. Results: CaP paste produced significantly lower SBS values than PA (p < 0.01), yet sufficient for clinical use. PA etching caused often cracked enamel surfaces with excessive retention of adhesive remnants (mainly ARI scores 2 and 3). Contrarily, enamel treated with the experimental CaP paste exhibited smooth, unblemished surfaces mostly clean of adhesives residues (scores 0 and 1). Conclusion: a newly developed CaP paste in a capsule formula fosters clinically adequate bracket adhesion with a sustained bonding performance, allows a harmless bracket removal with minimal or no adhesive residues on debonded surfaces; thus, it can be introduced as a suitable alternative to PA.
The study analyzed the current situation of public hospitals in the capital of Baghdad exclusively and diagnosed the resources available; especially after the high demand for these hospitals as a result of the citizen’s need to review the hospital to take care of them, especially after the Corona pandemic. Eight major hospitals in Baghdad were selected to determine the current reality of providing fire safety tools or equipment and what are the preventive measures needed to reduce it. The results after practical study showed many defects and weaknesses in the current situation due to their reliance on the traditional management to manage and provide all preventive measures and safet
Air pollution from various sources is one of the most serious environmental problems, especially after pollutants are deposited on the surface of the soil and leaves of the plants and then transferred to the rest of the plant and entering food chains. The present study was conducted to determine the effects of air pollution on different biochemical parameters in Eucalyptus sp. and calculation the Air Pollution Tolerance Index. The selected plant leaves were collected from five sites, four of them within the city of Baghdad, namely Al-Jadriya, Al-Andlous, Al-Doura and close to the private generators to represent the urban areas and Abu Ghraib site to represent the rural area. The leaves were taken on a seasonal basis for the period from Octo
... Show MoreIn the Name of God, the Most Gracious, the Most Merciful
Praise be to God, who taught the pen anthropology unless he knows, and peace and blessings be upon the master of bullying, and the imam of the eloquent Prophet Muhammad, the sincere and faithful, and his family and companions as a whole and whoever followed him to the Day of Judgment. And after:
The science of grammar is among the most important of all language sciences at all, if not the most important of its sciences, due to the multiplicity of its doctrines and schools, the diversity of its methods, its phenomena and subjects, as well as the connection of this science with the most honorable languages,
An experiment was carried out in pots under open field conditions in the fall seasons of 2017 and 2018 at the College of Agricultural Engineering Sciences, University of Baghdad, for improving field emergence and drought stress tolerance in sorghum. Three factors were studied. 1st factor was three cultivars (Inqath, Rabeh and Buhoth70). 2nd factor was primed and unprimed seed. 3rd factor was represented by the irrigation intervals every 2, 4 and 6 days. Randomized complete block design with four replicates was used. The results showed that Buhoth 70 cultivar had a significant superiority compared to others in traits of the first and final count of emergence, emergence energy and emergence rate index (54.2%, 26.7%, 1.747 and 70.7 % d
... Show MoreInternal conversion coefficients (ICC) and electron–positron pair conversion coefficients (PCC) for multipole transition of the core nucleus 88Sr have been calculated theoretically. The calculation is based on the relativistic Dirac–Fock (DF) solutions using the so called ‘‘Frozen Orbital’’ approximation, takes into account the effect of atomic vacancies created in the conversion process, covering a transition energies of 1–5000 keV. A large number of points were used to minimize any errors due to mesh-size effects. The internal conversion coefficients display a smooth monotonic dependence on transition energy, multipolarity and atomic shell. Comparing the values of PCC to ICC, it is interesting to note, that the energy dep
... Show MoreThis paper investigated in the numerical simulation model to calculate the Earth magnetic field components at north provinces of Najaf city (Longitude 44.316 o -44.3592o E and Latitude 32.0508o - 32.0256o N). The components of the Earth magnetic field (total intensity (F), horizontal intensity (H), declination (D), inclination (I), the north component(X), the east component(Y), and Down component(Z)) were found by using spherical harmonic world magnetic model (WMM2010). A great deal of anomaly has been discovered in all components of the Earth magnetic field at the selected region (Long. 44.345o-44.335o E, Lat.32.042o-32.032o N) using Kriging method.
... Show MoreThe products of the surrealist school since its inception to this day have greatly influenced art in the world, so we find many artists around the world invested in their visual texts the forms generated by surrealism, and here the researcher raises several questions: What are the formal vocabulary that directly or indirectly refers to Self-used by the surrealist painter? Was the surrealist form understood as intended by the movement? In these questions, the research problem is summarized. The importance of it lies in identifying the references to the form of the human self, which are related to the psychological field in the works of the surrealists, especially Salvador Dali. Then the researcher chose his research community from the wor
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