In this research, nanocomposites of poly(methyl methacrylate) (PMMA) and a mixture of nano silica (SiO2) and nano zirconia (ZrO2) were prepared in different weight percentages of the nano fillers to improve some of the properties of PMMA resin to be used as a denture base material. The nano filles were surface modified with a coupling agent and added to the PMMA in different amounts. Impact strength, transverse strength, hardness and roughness were tested for both control and experimental groups. The results indicate that PMMA/silica/zirconia nanocomposites, prepared with 5% by weight of both types of fillers, had a slight increase in impact strength, transverse strength and hardness with only an insignificant increase in roughness. This kind of composite material may have the potential for application in dental practice.
Background: Adjustment of any premature occlusal contact of any zirconia restoration requires its polishing or glazing in order to restore the smoothness of the restoration. The objective of this in vitro study was to evaluate the effects of different polishing systems and glazing on the surface roughness of full-contour zirconia. Material and methods: Forty disks (diameter: 8 mm, thickness: 6.4 mm) were prepared from pre-sintered full-contoured zirconia block; they were colored and sintered in a high-temperature furnace at 1500ËšC for 8 hours. The specimens were then leveled and finished using grinding and polishing machine and adjusted using diamond disk. The specimens were then randomly divided into four groups (n=10), group I involves
... Show MorePulsed laser ablation in liquid (PLAL) has become an increasingly important technique for metals production and metal oxides nanoparticles (NPs) and others. This technique has its many advantages compared with other conventional techniques (physical and chemical). This work was devoted for production of zirconia (ZrO2) nanoparticles via PLAL technique from a solid zirconium target immersed in a wet environment in order to study the effect of this environment on the optical properties and structure of ZrO2 nanoparticles. The solutions which used for this purpose is distilled water (D.W). The produces NPs were characterized by mean of many tests such as UV-visible (UV-Vis.), transmission electron microscope (TEM) and Z-Potential. The UV-Vis.
... Show MoreBackground: Genioglossus advancement is a surgical procedure to advance the tongue in some patients with obstructive sleep apnea syndrome.The important step in this procedure is that of accurately capturing the bone segment attached to the genioglossus muscle to avoid complications such as mandibular fracture, devitalization of the inferior incisor roots, and incomplete incorporation of the genioglossus Materials and Method: Computed tomography scans were taken for 53 Iraqi adult patients (28 male and 25 female) range from (18-35) years with skeletal class I classification and intact anterior mandible dentition included in this study using sagittal and axial sections. The measurements were done for genial tubercle and anterior mandibular re
... Show MoreThe bacterial contamination of lipsticks and face cream may become a great important matter in the medical laboratories. The present study was designed to determine the types of bacterial contamination in the face cream and lipsticks of undergraduate students. Also, the study aimed to determine the sensitivity of the isolated bacteria against many antibacterial agents. The study included 190 swabs samples from 190 face cream and lipsticks samples of the females’ students from five departments in the Medical Technology Institute, Almansour, Middle Technical University were collected in February 2018. The swab samples were collected with sterile condition and cultured on enriched Blood agar and MacConkey agar. Serial dilutions were made up
... Show MoreBackground: Bladder cancer (BC) is the most common malignant tumor in the urinary tract and the tenth most common malignancy worldwide. Exosomes are 40–100 nm-diameter nanovesicles that are either released straight from the plasma membrane during budding or merged with the plasma membrane by multivesicular bodies. Objectives: To assess the proportion of serum and urinary Exosome levels in urinary bladder cancer patients, as well as their impact on the disease. Methods: From January 2023 to June 2023, a total of 45 samples of blood and urine were collected from individuals diagnosed with bladder cancer at the Ghazi Hariri Hospital for Specialized Surgery. They included 45 male and female patients, varying in age, as well as 45 heal
... Show Morein this paper the second order neutral differential equations are incestigated are were we give some new suffucient conditions for all nonoscillatory
Porcelain is one of the most important ceramic materials with a wide range of traditional and technical applications. Since most mixtures of porcelain have a high sintering temperature, bentonite has been added in this research to improve the characteristics of sintering and burning. The porcelain mixture consisted of the following Iraqi raw materials: 30% wt kaolin, 30 wt% non-plastic clay (grog), 10% wt sodium feldspar, 10 wt% potassium feldspar and 20 wt% flint. After the mechanical mixing process and transfer the powder mixture to the slurry by adding distilled water, then different weight percentage of the sodium bentonite(0, 2.5, 5, 7.5 and 10) wt% was added. The specimens were prepared by using the solid casting m
... Show MoreAlginate from Large brown seaweeds act as natural polymer has been investigated as polymer and has been added to concrete in different percentages ( 0% , 0.5% , 1% and 1.5% ) by the cement weight and the study show the effect of using alginate biopolymer admixtures on some of the fresh properties of the concrete (slump & the density fresh) also in the hardened state ( Compressive strength , Splitting tensile strength and Flexural strength ) at 28 days. The mix proportion was (1:2.26:2.26) (cement: sand: gravel) respectively and at constant w/c equal to 0.47. The results indicate that the use of alginate as a percent of the cement weight possess a positive effect on fresh properties of co
... Show MoreABSTRACT : This research involves the synthesis of five to seven heterocyclic compounds starting with Schiff’s bases which derived from oxime as a starting material. 1.3-oxazepine derivatives were prepared from adding different anhydrides to the Schiff bases, tetrazole and thiazolidinone derivatives synthesized from add sodium azide and thioglycolic acid to the same Schiff’s bases as a five members ring. Pyrimidine derivatives were prepared after the reaction of the azomethine group with acetyl chloride and then urea and thiourea to synthesis on derivatives contain the six members ring. Another step included identified and confirmed these compounds by FT- IR, 1HNMR, TLC and 13CNMR finally, step included the assay of biological activity
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