Background: Glass ionomers have good biocompatibility and the ability to adhere to both enamel and dentin. However, they have certain demerits, mainly low tensile and compressive strengths. Therefore, this study was done to assess consistency and compressive strength of glass ionomer reinforced by different amount of hydroxyapatite. Materials and Methods: In this study hydroxyapatite materials were added to glass ionomer cement at different ratios, 10%, 15%, 20%, 25% and 30% (by weight). The standard consistency test described in America dental association (ADA) specification No. 8 was used, so that all new base materials could be conveniently mixed and the results would be of comparable value and the compressive strength test described by British standard specification for zinc polycarboxylate cement was used in this study. Results: Different consistencies of materials produced a disc of varying sizes. The amount of the powder (in milligram) was mixed with 0.5 ml of liquid to produce a consistency giving a disc of 3 cm±1mm in diameter were 500 mg for glass monomer cement, 450 mg for glass ionomer cement reinforced by 10%, 5% and 30% of hydroxyapatite and 350 mg for glass ionomer cement reinforced by 20% and 25% of hydroxapatite. The results showed that the glass ionomer cement reinforced by hydroxyapatite has higher compressive strength than conventional glass ionomer. Conclusion: The addition of hydroxyapatite to conventional glass ionomer requires less powder to liquid ratio. Addition of hydroxyapatite to glass ionomer cement increased its compressive strength.
The dimensions of bubbles were measured in a stirrer tank electrochemical reactor, where the analysis of the bubble size distribution has a substantial impact on the flow dynamics. The high-speed camera and image processing methods were used to obtain a reliable photo. The influence of varied air flow rates (0.3; 0.5; 1 l/min) on BSD was thoroughly investigated. Two types of distributors (cubic and circular) were examined, and the impact of various airflow rates on BSD was investigated in detail. The results showed that the bubbles for the two distributors were between 0.5 and 4.5 mm. For both distributors at each airflow, the Sauter mean diameter for the bubbles was calculated. According to the results, as the flow rate raised, the bubb
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Phenotypic And genotypic characteristics of Salmonella enterica serotype Typhi have been determined for 29 isolates, from Baghdad in 2007. Conventional typing methods were performed by biochemical tests, and antimicrobial susceptibility test. Molecular typing performed by analysis plasmid DNA beside using the Random Amplified Polymorphic DNA (RAPD-PCR). For the latter, two universal primers that have selected for the high discriminatory power were used for RAPD analysis. All isolates were belong one biotype according to the differention by their ability to decarboxylat lysine, 29(100%) were lysine (+). All the isolates were susceptible to the Antibiotics used. However, all the strains free of plasmids. RAPD was capable of grouping the strai
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Proteinases (E.C.3.4.21) family are widely distributed in the nature; it was present in animals tissues , plants and microbial cell . Protease was purified from Zahdi seed (Phoenix dactylifera L.) by several steps included ammonium sulphite ppt (75%) saturation and dialyzed against the 80mM sodium phosphate buffer at pH 7.5 . The enzyme specific activity was 407.62 unit/mg protein. The obtained extract was purified by DEAE-Cellulose column followed by gel filtration through Sephacyl S-200 column .The enzyme specific activity ,yield and purification fold were 1873.49 unit/mg protein, 22.99 and 58.42% respectively. The results of protease characterization showed that the molecular weight was 25118 daltons as determined by gel f
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To investigate the prevalence of true periodontal chief complaints (CC) and the factors affecting their reporting by patients with periodontal diseases (PD).
This cross‐sectional study was based on retrospective analysis of available periodontal records. Different personal and demographic variables were obtained from these records including CC, age, gender, working status, past medical/dental history, smoking status and diagnosis. In addition, clinical parameters of plaque index, gingival index, probing pocket depth (PPD), and number of missing teeth. Periodontal CC were r
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The molar ratio(x) of Li-Ni ferrites in the formula Li0.5-0.5xNixFe2.5-
0.5xO4 was varied in range 0.1-1.0 by hydrothermal process. The
XRD, SEM, and TEM tests were conducted to examine the samples
crystalline phase and to characterize the particles shapes and sizes.
The high purity spinel structure was obtained at med and high x
values. SEM and TEM images showed the existence of different
ferrite particles shapes like nanospheres and nanorods. The
maximum particle size is around (20nm). These size encourage
occurrence of super paramagnetic state. The reflection loss and
insertion loss as microwave losses of Li-Ni ferrite-epoxy composite
of 1mm thickness and mixing ratio 39.4 wt was investigated. The
mini
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This search include the synthesis of some new 1,3-oxazepine derivatives have been prepared, starting from reaction of L-ascorbic acid with dry acetone in presence of dry hydrogen chloride afforded the acetal (I). Treatment of the latter with p-nitrobenzoyl chloride in pyridine yielded the ester (II) which was dissolved in (65%) acetic acid in absolute ethanol yielded the glycol (III). The reaction of the glycol (III) with sodium periodate in distilled water at room temperature produced the aldehyde (IV). The compound (V) [4-(1,3-dioxoisoindolin-2-yl)benzoic acid] was synthesized by reaction p-aminobenzoic acid and phthalic anhydride in presence of (gla. CH3COOH). Reaction of compound (V) with thionyl chloride produced [4-(1,3-dioxoisoindoli
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Nowadays, there is increased interest in the biosynthesis of microbial melanin related to their numerous biological functions and applications in many fields, especially in medical fields, including immune-modulating, antimicrobial antibiotic, antiviral antivenin, anticancer, antitumor activity, and anti-biofilm activity. Pyomelanin is a hydrophobic macromolecule that is typically dark brown or black in color, formed by the oxidative polymerization of phenolic or indolic compounds. Pyomelanin is reported to be safe for consumption, thus providing a crucial strategy for biocontrol of biofilm. Furthermore, natural pyomelanin is known as a potent antioxidant, photoprotective, and free radical scavenging. Objective: This study focuses on the
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Research Summary
Praise be to God, and may blessings and peace be upon our master Muhammad al-Mustafa, his family, his companions, and those who follow his gift until the Day of Judgment.
As for the dimension: This is a historical description of my conquest (Al-Khandaq and Ba
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