Background: With the increasing demands for adult orthodontics, a growing need arises to bond attachments to porcelain surfaces. Optimal adhesion to porcelain surface should allow orthodontic treatment without bond failure but not jeopardize porcelain integrity after debonding.The present study was carried out to compare the shear bond strength of metal bracket bonded to porcelain surface prepared by two mechanical treatments and by using different etching systems (Hydrofluoric acid 9% and acidulated phosphate fluoride 1.23%). Materials and Methods: The samples were comprised of 60 models (28mm *15mm*28mm) of metal fused to porcelain (feldspathic porcelain). They were divided as the following: group I (control): the porcelain surface left untreated and glazed, group II (Diamond bur group): the porcelain surface was treated with fine diamond bur at speed of 350000 rpm for 20 seconds, group III (Red stone bur): the porcelain surface was treated with coarse red stone bur at speed of 8500 rpm for 20 seconds. Each group consists of 20 samples, then each group subdivided into two subgroups; one treated with acidulated phosphate fluoride 1.23% and the other subgroup treated with Hydrofluoric acid 9 % with silane coupling agent. Results: The result of this study revealed that there was very high significant difference among all tested groups and the highest shear bond strength was for diamond bur group with HFA and Silane (8.67 MPa), the 2nd highest strength was for control group with HFA and Silane (7.52 MPa), the 3rd was (7.38 MPa) in red stone bur with HFA and Silane, the least shear bond strength values were obtained for subgroups treated with acidulated phosphate fluoride gel 1.23%. Conclusions: The most reliable procedure for bonding orthodontic brackets to the porcelain surfaces is through the surface treatment combinations of mechanical roughening by using diamond bur, 9% Hydrofluoric acid and Silane coupling agent application.
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Aspartate aminotransferase was purified from urine and serum of patients with type 2 diabetes in a 2 steps procedure involving dialysis bag and sephadex G-25 gel filtration (column chromatography). The enzyme was purified 346.23 fold with 1467% yield and 3.46 fold with 142.85% yield in urine and serum of patients with type 2 diabetes respectively. The purified enzyme showed single peak. The results of this study revealed that AST activity of type 2 diabetes urine and serum increased significantly (p<0.001) compared with control group.
Background: Periodontal diseases (PD) are inflammatory conditions of the tissues supporting the teeth, most often gingivitis and periodontitis. Maxillary chronic rhinosinusitis (MCRS) is the inflammation of the maxillary sinuses which is last for at least 12 consecutive weeks duration. Aims of study: Distribution of periodontal diseases among patients with Maxillary chronic rhinosinusitis according to gender and age. Materials and methods: Males and females subjects (25-45 years), divided into two groups; 150 patients suffer from MCRS and 130 subjects without MCRS. Clinical periodontal parameters; Plaque Index (PL.I), Gingival Index (G.I), Probing Pocket Depth (PPD), Clinical Attachment Level (CAL) and Bleeding On Probing (BOP) recorded f
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It has been revealed previously that chronic liver disease (CLD) may be associated to hormonal fluctuations. The current study, therefore, aimed to evaluate some hormones in CLD patients compared with non-CLD individuals. This case control study was conducted at Gastroenterology and Hepatology Teaching Hospital, Medical city, Baghdad, Iraq during December 2021 to May 2022. One hundred and twenty male patients with CLD (age:14-75 years) and 120 control males (age: 24-70 years) were involved in this study. Serum samples were taken from all individuals and were then analysed for many tests which included hormones (Cortisol, testosterone, prolactin, insulin and thyroid stimulating hormone TSH); biochemical analysis (Prothrombin time
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Abstract
The mine object for this research is determine the nature of the relation and effect between Human resources management strategic to less the work stress , Human resources management strategic represent a set of procedures and practices to manage the human resources at the organization. the stress of work effect on the performance of the human resources , al rasheed bank select to applied the qustioneer on the 32 person the work on the sebaa branch , using the qustioneer as a tool to collect data that is design according some of the standards and make the validity and stability. to analyses this data by using spss for computation " percentage , mean , standard , deriation
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(13)
Experimental work has been performed on three capillary tubes of different lengths and diameters using R-12 and R-134a. The test also studies the effect of discharge and speed of evaporator fan. The results clearly showed that refrigerant type and discharge significantly influence the temperature drop across the capillary tube. While the speed of evaporator fan has small effect. Experimental results showed that the temperature gradient for the two refrigerants are the same, but after approximatly one meter the temperature gradient of R-134a is steeper than R-12.
Background:This is a prospective study of three children presented to us in the Orbital clinic in AL ShahidGazi Al Hariri Hospital with painless proptosiswith suspension of Hydatid disease.Objectives: : Orbital hydatid disease is a rare lesion accounting for less than 1% of the total lesions of the body (1, 2). Orbital cysts presented as a primary lesion in our study which is rare to have such lesion without involvement of other organs (3). Humans represent the intermediate host where the commonly affected organ are liver and the lung (10-15%) (4). Methods:This is a prospective study of three Children presented to us in the Orbital clinic in Al Shahid Ghazi Alhariri Hospital with painless proptosis with suspension of Hydatid disease, dep
... Show MoreFour mixed ligand complexes were prepared from 1,10-phenanthroline (Phen), 5-chlorosalicylic acid (CSA), and anthranilic acid (Anthra) dissolved in aqueous ethanol at a ratio of (1:1:1:1) M: Phen:CSA: Anthra, M(II)= Cu, Zn, Cd, and Hg. The prepared compounds were analyzed by flame atomic absorption, FT—IR, UV-Vis, and spectroscopic methods, as well as conductivity measurements and magnetic properties. After analyzing the prepared compounds using the acquired data, the complexes formed by mixing ligands were concluded to adopt an octahedral geometry. That study has been conducted to test the inhibitory effectiveness of the complexes (1,10-Phenanthroline (Phen), 5-Chlorosalicylic acid (CSA), Na[Cu(Phen)(CSA)(Anthra), Na[Zn(Phen)(CSA)(Anthr
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