Background: The objective of this in vitro study was to evaluate the vertical marginal fit of crowns fabricated with ZrO2 CAD/CAM, before and after porcelain firing cycles and after glaze cycles. Materials and Methods: An acrylic resin model of a left maxillary first molar was prepared and duplicated to have Nickel-Chromium master die. Ten die stone dies were sent to the CAD/CAM (Amann Girrbach) for crowns fabrication. Marginal gaps along vertical planes were measured at four indentations at the (mid mesial, mid distal, mid buccal, mid palatal) before (Time 0) and after porcelain firing cycles (Time 1) and after glaze cycles (Time 2) using a light microscope at a magnification of ×100. One way ANOVA LSD tests were performed to determine whether the mean and standard deviation of sub group Time 2. Results: The mean values of the ZrO2 CAD/CAM Time 0 were (6.77?m), Time 1(8.75?m) and Time 2(10.62 ?m). One way ANOVA test revealed highly statistical significance(P<0.01). LSD test results showed that there is highly significant difference between time (0) and time (2), while there is no any significant difference between time (0) and time (1), and between time (1) and time (2). Conclusions: Within the limitations of this study, it was concluded that the ZrO2 CAD/CAM demonstrated acceptable marginal fit; The porcelain firing and the glaze firing cycles affected the marginal gap
The arrival of Russian President Vladimir Putin to power in the Russian Federation is an important factor in delineating a new approach to Russian policy towards regions that have great strategic importance affecting its national security. Therefore, NATO's progress eastward towards these regions prompts Russia to delineate a new strategy to confront this progress as well as preserving its control in the near neighboring regions represented by the countries of Eastern Europe, especially after the changes that occurred in those regions following the color revolutions that swept the region, such as the first application of this Russian policy in 2014, through the annexation of Crimea, and the latest military operations in Ukraine i
... Show MoreBackground: The elimination of the microorganisms from the root canal systems, an important step for the successful root canal treatment. This study was conducted to evaluate the antibacterial effectiveness of the photoactivated disinfection by using the toluidine blue O and a low- energy light emitting diode (LED) lamp . Materials and method: Sixty single rooted extracted teeth were decoronated, instrumented, irrigated, sealed at the apex and contaminated with endodontic anaerobic bacteria for 7 days to form biofilms in prepared root canals. Group I. Twelve teeth were medicated by photosensitizer (toluidine blue O) solution activated by diode lamp (FotoSan; CMS Dental, Copenhagen, Denmark).Group II. Twelve teeth were medicated by the tricr
... Show MoreOil well drilling fluid rheology, lubricity, swelling, and fluid loss control are all critical factors to take into account before beginning the hole's construction. Drilling fluids can be made smoother, more cost-effective, and more efficient by investigating and evaluating the effects of various nanoparticles including aluminum oxide (Al2O3) and iron oxide (Fe2O3) on their performance. A drilling fluid's performance can be assessed by comparing its baseline characteristics to those of nanoparticle (NPs) enhanced fluids. It was found that the drilling mud contained NPs in concentrations of 0,0.25, 0. 5, 0.75 and 1 g. According to the results, when drilling fluid was used without NPs, the coeff
... Show MorePatch in transdermal drug delivery(TDDS) used to overcome the hypodermic drawback, but these patch also have absorption limitation for hydrophilic and macromolecule like peptide and DNA. So that micronized projection have the ability for skin penetration developed named as microneedle. Microneedle drug delivery system is a novel drug delivery to overcome the limitation of TDDS like skin barrier restriction for large molecule. Microneedle patch can penetrate through skin subcutaneous into epidermis, avoiding nerve fiber and blood vessel contact. There are many type of microneedle patch like solid, polymer, hallow, hydrogel forming microneedle and dissolving microneedle with different method of microfabrication
Background: The study aimed to investigate the effect of different techniques of en masse retraction on the vertical and sagittal position, axial inclination, rate of space closure, and type of movement of maxillary central incisor. Materials and methods: A typodont simulation system was used (CL II division 2 malocclusion). Three groups were used group 1(N=10, T-loop), group 2(N=10, Time-Saving loop), and group 3(N=10, Microimplant). Photographs were taken before and after retraction and measurements were made using Autodesk AutoCAD© software 2010. Kruskal-Wallis one-way analyses of variance and Mann-Whitney U test (p?0.05) were used. Results: The rate of space closure showed no significant difference among the three groups (p?0.05), whi
... Show MoreBackground: The isthmus is a difficult area in the root canal complex to manage. The research aimed to evaluate the efficiency of three different obturation techniques (lateral condensation, EandQ (thermoplasticized gutta percha system) and Soft Core (thermoplasticized core carrier gutta percha system)) to obturate the isthmus area of roots prepared by two different instrumentation techniques (rotary ProTaper universal and ProTaper Next systems). Material and method: Sixty freshly extracted teeth were randomly divided into two main groups (A and B) of 30 teeth each. Group A was prepared by rotary ProTaper Universal whereas group B was prepared by ProTaper Next system. Each main group was then randomly subdivided into three subgroups of 10 t
... Show MoreThe investment climate is the main engine of economic development. If an appropriate and attractive investment climate is created that takes into account economic, administrative, political and environmental issues, it will contribute to the development of industry, transfer of technology, diversification of agricultural production, increased productivity, the promotion of a green economy and support for sustainable and inclusive growth. Thus, analyzing the investment climate of a country can provide reasons and roots for the complexity of the problems in the economy. In the Iraqi economy, the problem has not been rooted in the economy, but the roots of the problem are deeper and inherent in the management of the economy. Investm
... Show MoreThe research current (Comment formal for Hruvijat in contemporary Iraqi porcelain). In an attempt to study the Arab character that inspired the Iraqi artist of all intellectual its terms of reference and stylistic by taking advantage of the cultural heritage and the rebuilding of the character to create a system ride of relationships that focus on structural body ceramic body ideas and multiple implications are invested in the structural fabric of the products of contemporary ceramic .vdila for ways to achieve and processing techniques and transmission of functional specificity (blogging) and cosmetic particularly to semantics derive from the content and expresses itself templates ceramic raw materials and by building works of art in pla
... Show MoreIn this work, Soda Lime Glass (S.L.G.) powder was used ,as
fluxe in traditional porcelain instead of feldspar. Two ceramics
porcelain were compared; commercial or traditional porcelain that
content of 50wt % kaolin, 25wt % quartz, and 25wt % feldspar.
Feldspar mass was substituted by scraps soda lime glass yielding a
new porcelain composition, to determine the softening points and
then the effect of glass addition on porcelain firing process.
Eight samples, for each patch, were prepared and 8wt % water
was added. The resulting composite blends were then die pressed at
2N, to produce disk specimens with diameter of 1.5 cm, and then
they were sintered at (1000, 1100, 1200, 1250,1300,1350,1400 and
1450) ˚C,
Liquisolid compact is the most promising technique for increasing dissolution rate and bioavailability of poorly soluble drugs.Clopidogrel bisulfate is an oral antiplatelets used for treatment and prophylaxis of cardiovacular and peripheral vascular diseases related to platelets aggreagation.Clopidogrel has low solubility at high pH media of intestine and low bioavailability of a bout 50% after oral doses.The purpose of this work was to enhance dissolution pattern of clopidogrel through its formulation into liquisolid tablets.A mathematical model was used to calculate the optimum quantities of tween 80 , carrier (Avicel PH 102) and coating material (Aerosil 200) needed to prepare acceptably flowing and compactible powder mixtures.The liq
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