Background: Denture relining is the process of resurfacing of the tissue side of the ill fitting denture, the bond strength at the relining-denture base interface is most important for denture durability.The aim of present study was to evaluate the shear bond strength between the thermosens as relining material and different denture base materials that bonded by thermo fusing liquid. As this corrective procedureis the common chair side procedure in the dental clinic. Material and method: Sixty samples were prepared and divided into three main groups according to the type of denture base materials.Group (A) referred to the heat cure acrylic samples which consisted of 20 samples. Group (B) referred to the high impact acrylic samples which consisted of 20 samples. Group (C) referred to the thermosens samples which consisted of 20 samples. All groups then subdivided into two groups; each one consists of 10 samples, according to the surface roughness: (A1, B1and C1 for groups with surface roughness and A2, B2 and C2for groups without surface roughness). Each sample consisted of two similar parts represent the denture base material each part of the sample was designed with dimensions of (70mm X 12mm X 5mmlength, width and depth respectively) having a stopper of depth 3mm. One part of the sample was placed on the other in a manner thatleaving a space between them of dimensions (12mm X 12mm X 3mm length, width and depth respectively) to sandwich the relining material. Results: The results showed that the thermosens samples had the highest value of shear bond strength followed by the high impact acrylic samples, then heat cure acrylic samples which had the lowest value of shear bond strength. The results of present study showed that rough samples had reducedshear bondstrength in comparison with the smooth samples of the same denture base material.
In this work, varying compositions of SiO2 micro filler were added
with the Polyvinyl Chloride (PVC) and samples have been prepared
using film casting technique. The results have been analyzed and
compared for PVC samples with (1 wt%, 3 wt%, 5 wt% and 10 wt%)
SiO2 micro filler. Mechanical characteristics such as tensile strength,
elongation at break and Young`s modulus were measured for all the
samples, where the tensile strength was increased from 8.39 Mpa for
purified PVC to 16 Mpa for 3% SiO2/PVC composite. Also, thermal
conductivity measurement values illustrated that composite materials
have a good thermal insulation at 10 wt. %, thermal conductivity was
decreased from 0.1684 W/m.
The stress(Y) – strength(X) model reliability Bayesian estimation which defines life of a component with strength X and stress Y (the component fails if and only if at any time the applied stress is greater than its strength) has been studied, then the reliability; R=P(Y<X), can be considered as a measure of the component performance. In this paper, a Bayesian analysis has been considered for R when the two variables X and Y are independent Weibull random variables with common parameter α in order to study the effect of each of the two different scale parameters β and λ; respectively, using three different [weighted, quadratic and entropy] loss functions under two different prior functions [Gamma and extension of Jeffery
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Small molecules drug conjugate mutual prodrug design (SMDC) composed of folate and lethal agent conjugate, rigidly bonded via hydrophilic bridge and self immolative disulfide bond ; represent new interesting approaches for cancer treatment , the component of SMDC intended for targeting folate receptor , along with greater conservation of component until reaching the target tumor tissue . The designing and synthesis of compound VI and VIII derived from 6-Mercaptopurine (6-MP) and Methotrexate ( MTX) conjugate altogether as mutual prodrugs were processed forward successfully by multistep reaction procedures , and by Thin Layer Chromatography (TLC) for
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Heterogeneous organic compounds play an important role in our daily life as they contribute in many medical and industrial fields and are in continuous development as a result of the preparation of new derivatives with different properties. From this premise, the goal of this work appears, which is preparation of (four, five, six, and seven) membered ring systems derived from furfural, by its reaction with different aromatic aldehydes, and record their antioxidant activity by using free radical scavenging method of DPPH radicals. The new ring systems are synthesized by reacting the prepared Schiff-bases with different ring closure agents (chloroacetyl chloride, mercaptoaceticacid, anthranilic acid, and phthalic anhydride), the prep
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Background: Studies discussing the correlation between biochemical markers of bone turnover and the diagnosis of osteoporosis in postmenopausal Iraqi women are rare. This study is devoted to find out the significance of serum osteocalcin (OC) and osteopontin (OPN) levels with the incidence of osteoporosis and its major complication (fracture).Objectives: to investigate the significance of bone turnover biochemical markers; serum osteocalcin and serum osteopontin in evaluating osteoporosis for postmenopausal Iraqi women with and without history of vertebral fracture, as well as to explore the relationship of these markers with bone mineral density (BMD).Methods: Fifty seven postmenopausal women whose ages are fifty years old and over, cat
... Show MoreBacterial infections pose an ongoing challenge due to resistance developed by infectious bacteria. So much research targeting designing new antibacterials is published annually. Our goal is to synthesize compounds that have given antibacterial activity according to molecular docking against the chosen target protein and that have acceptable ADMET properties that can be synthesized and used in the future. New 2-(5-methoxy-1-(4-chlorobenzene)-2-methyl-1H-indol-3-yl)acetohydrazide derivatives’ antibacterial efficacy against two common strains of Gram-negative and Gram-positive microorganisms has been developed, produced, and investigated. Sophisticated, modern analytical methods, including ATR-FTIR and 1H NMR spectroscopy, were used
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One of the major problems facing the road construction engineer is the collapsible granular soil which may be used for embankment construction. Problems appears when such compacted soil come in touch with water, it exhibits cracking and uncontrolled settlement. Collapsible soils are defined as any unsaturated soil that goes through a radical rearrangement of practice and great loss of volume upon wetting, with or without additional loading. An attempt has been made in this investigation to stabilize the collapsible soil of Nasiriya with asphalt emulsion. Specimens of pure and asphalt emulsion stabilized soil have been prepared using optimum fluid content and tested. The first group of specimens of (60x60x20) cm have been tested for direct s
... Show MoreThe research involves using phenol – formaldehyde (Novolak) resin as matrix for making composite material, while glass fiber type (E) was used as reinforcing materials. The specimen of the composite material is reinforced with (60%) ratio of glass fiber.
The impregnation method is used in test sample preparation, using molding by pressure presses.
All samples were exposure to (Co60) gamma rays of an average energy (2.5)Mev. The total doses were (208, 312 and 728) KGy.
The mechanical tests (bending, bending strength, shear force, impact strength and surface indentation) were performed on un irradiated and irrad
... Show MoreOne of the most difficult tasks in modern medical societies is the process of identifying a cure for many infectious diseases caused by drug-resistant microbes. Therefore, it has become necessary to discover new compounds that work in this regard. The currently prepared Schiff base, derived from thiazole, has a biological activity against bacteria and biofilms and its activity increases when it is associated with copper, zinc and platinum ions and forms metal complexes. This study highlights the synthesis and evaluation of novel biological compounds as inhibitors of bacterial growth and biofilms. A three newly complexes are resulting from the reaction of a new Schiff base ligand (LC) with metal ions (Zn, Cu, Pt). The new ligand (LC)
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