ABSRTACT Background: Soft liner material is become important in dental prosthetic treatment. They are applied to the surface of the dentures to achieve more equal force distribution , reduce localized pressure and improve denture retention by engaging undercut . So the aim of the study is to evaluate the effect of different surface treatment by air-abrasion AL2O3 and laser treatment with CO2 laser on improving the shear bond strength of the denture liner to acrylic denture base material . Materials and methods: the 30 specimens of heat cured acrylic denture base material (high Impact acrylic )and heat cured soft liner (Vertex ,Nether Lands )were prepared for this study .They were designed and divided according to type of the surface treatment 10 specimens for each group and as follows :Group I without any treatment (control group ), Group II was treated with air-abrasion (AL2O3). While group III was treated with CO2 laser which has continuous pulses with wave length(10.6) micro-meter for (15) seconds . Results: The results revealed that lowest mean values in shear bond strength the specimens treated with AL2O3 (0.498 N/mm2)and control group (0.569 N/mm2)and the highest mean values for the specimens treated with CO2 laser (0.648 N/mm2) . Conclusion: within the limitation of this study ,CO2 laser surface treatment of the heat cure acrylic denture resin with soft liner material resulted in highly significantly increased in shear bond strength values than control and AL2O3 .
Moisture damage is a primary mode of distress occurring in hot mix asphalt (HMA) pavements in Iraq. Because of the loss of bond, or stripping, caused by the presence of moisture between the asphalt and aggregate, which is a problem in some areas and can be severe in some cases, it is requires to evaluate the design asphalt mixture to moisture susceptibility. Many factors such as aggregate characteristics, asphalt characteristics, environment, traffic, construction practices and drainage can contribute to stripping. Asphalt concrete mixes were prepared at their optimum asphalt content by superpave system and then tested to evaluate their engineering properties, which include tensile strength, resilient modulus, and perman
... Show MoreThe research aims to identify the possibility of applying environmental fines to commercial shops and restaurants to reduce the environmental pollution represented by the wastes generated from them. The research sample was divided into two groups, including the first (20) commercial shops (meat shops and slaughter it, fruits & vegetables, legumes and accessories) and second (30) Restaurant in the city of Baghdad on both sides of Karkh and Rusafa. The quality of the waste was classified into carton, plastic, aluminum, glass, paper, cork and food waste. The study revealed the possibility of applying environmental fines to restaurants and shops to reduce the waste generated from them throughout the year and to apply continuous monitorin
... Show MoreThe construction project is a very complicated work by its nature and requires specialized knowledge to lead it to success. The construction project is complicated socially, technically and economically in its planning, management and implementation aspects due to the fact that it has many variables and multiple stakeholders in addition to being affected by the surrounding environment. Successful projects depend on three fundamental points which are cost-time, performance and specifications. The project stakeholder's objective to achieve best specifications and the cost-time frame stipulated in the contract.
The question is, was the optimum implementation accomplished? The provision for the success of the project
... Show MoreThe interaction of interplanetary coronal mass ejections (ICME) with each other and with co-rotating interaction regions (CIR) changes their configuration, dynamics, magnetic field and plasma characteristics and can make space weather forecasting difficult. During the period of March 20–25, 2011, the Solar Terrestrial Relation Observatory (
Aqueous extract of poppy plant) Papaver nudicaule) with five concentrations (50, 100, 150, 200 and 250) mg/l were used to anesthetize fingerlings of the common carp Cyprinus carpio (Mean total length 8.91 ± 0.31 cm and mean total weight 7.72 ± 1.19 gm) instead of the traditional use of MS-222. Results showed that extracted solution of poppy have partial and overall anesthesia effect on these fishes with inverse relationship between the concentrations used and the time needed to reach partial and overall anesthesia, and also direct relationship between concentrations used and time needed for fish recovery. Best results were obtained by using a concentration of 250 mg/l, where time for partial anesthesia was 8 ± 1.52 m
... Show MoreThis study attempts to address the importance of communicative digitization in the field of various arts for the sake of continuity of shopping and aesthetic, artistic and intellectual appreciation of artistic achievements by the recipient on various places of their residence in light of the COVID 19 crisis, and to highlight the importance of the plastic arts of the Iraqi painter exclusively and how it expresses in a contemporary way the environment or life reality in Iraq in light of this crisis. With all its implications affecting the life reality from various aspects and methods of its negative and positive employment. As for the research procedures, the researcher reviewed the research methodology represented by the descriptive ana
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Background: The oral cavity is a complex environment, both structurally and functionally, the hard and soft tissues are in close a proximity. Oral tissues subjected to wear throughout the life, that threatened the vitality of the pulp or increase the sensitivity of dentinal tubules. One of the common dental problems is loss of enamel or cementum, which stimulate the nerve ending in or near the pulp and manifested as pain sensation. Aim of the study: This study had done to evaluate the effects of 980nm diode Laser in diameters reduction of exposed dentinal tubules analyze the results and morphological changes of irradiated dentine surface by FE-SEM (field emission scann
... Show MoreWe demonstrate a behavior of laser pulse grows through fiber laser inside and output cavity with a soliton fiber laser based on the multi-wall carbon nanotube saturable absorber (SA), we investigate the effects of a saturable absorber parameter on the mode-locking of a realistic Erbium fiber ring laser. Generalized nonlinear Schrodinger equation including the nonlinear effects as gain dispersion, second anomalous group velocity dispersion (GVD), self phase modulation (SPM), and two photon absorption used to describe pulse evolution. An analytical method has been used to understand and to quantify the role of the SA parameter on the propagation dynamics of pulse laser. We compute the chirp, power, width and phase of the soliton for range
... Show MoreEvaluating treatment effect on interferon-alpha in female patients with systemic lupus erythematosus: a case-control study
The study aims to identify the impact of the round-robin strategy on the logical thinking of fourth-year middle school students in chemistry. Two groups were employed: an experimental group consisted of (30) students who were taught according to the round-robin strategy, and the control group consisted of (30) students who were taught according to the traditional method. The researcher adopted the experimental design with partial control by preparing the visual thinking test tool, which consists of (20) multiple-choice items, it was applied as a post-test on the research sample. The result showed that there was a statistically significant difference in favor of the experimental group, which was taught according to the Round Robin s
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