Background: Prophylaxis methods are used to mechanically remove plaque and stain from tooth surfaces; such methods give rise to loss of superficial structure and roughen the surface of composites as a result of their abrasive action. This study was done to assess the effect of three polishing systems on surface texture of new anterior composites after storage in artificial saliva. Materials and methods: A total of 40 Giomer and Tetric®N-Ceram composite discs of 12 mm internal diameter and 3mm height were prepared using a specially designed cylindrical mold and were stored in artificial saliva for one month and then samples were divided into four groups according to surface treatment: Group A (control group):10 specimens received no surface polish and were subdivided into A1 (Giomer) and A2 (Tetric®N-Ceram). Group B: 10 specimens received polishing with Air polishing devise (APD) and were subdivided into B1 (Giomer) and B2 (Tetric®N-Ceram). Group C: 10 specimens received polishing with pumice and brush and were subdivided into C1 (Giomer) and C2 (Tetric®N-Ceram). Group D: 10 specimens were polished with pumice and rubber cup and were subdivided into D1 (Giomer) and D2 (Tetric®N-Ceram). Testing was done by means of profilometer and statistically analyzed using analysis of variance test (ANOVA), LSD and student t-test. Also samples were photographed by special orthoplane camera using light polarizing microscope. Results: The results showed a highly statistical significant difference in surface roughness among Giomer subgroups P<0.05. Also there was a highly significant difference P<0.05 when comparing Tetric subgroups according to type of surface treatment. Furthermore there was non-significant difference P>0.05 between groups according to the type of restorative material used. Conclusion: The use of prophylactic surface treatment significantly increased Giomer and Tetric ceram surface roughness and the use of rotating brush has shown the roughest surface among all other types of prophylactic protocols also Giomer had shown more surface roughness than Tetric ceram although the difference was not significant.
The cost-effective carbon cross-linked Y zeolite nanocrystals composite (NYC) was prepared using an eco-friendly substrate prepared from bio-waste and organic adhesive at intermediate conditions. The green synthesis method dependent in this study assures using chemically harmless compounds to ensure homogeneous distribution of zeolite over porous carbon. The greenly prepared cross-linked composite was extensively characterized using Fourier transform infrared, nitrogen adsorption/desorption, Field emission scanning electron microscope, Dispersive analysis by X-ray, Thermogravimetric analysis, and X-ray diffraction. NYC had a surface area of 176.44 m2/g, and a pore volume of 0.0573 cm3/g. NYC had a multi-function nature, sustained at a long-
... Show MoreThe problem of the research lies in finding aiding means that improve and facilitate learning artistic skills during the main part of a teaching sessions due to their great importance in developing the accuracy of forehand and backhand skills in tennis. Players are usually faced with difficulties at the beginning of learning due to lack of coordination in ball striking thus including a teaching aid will have a positive effect on learning some forehand and backhand skills. The research aimed at designing exercises using teaching aid in tennis as well as identifying the effect of these exercises on the accuracy of performing forehand and backhand shots in tennis. The researcher used the experimental method on (38) tennis players from Al Zewra
... Show MoreIn this study, lateral groundwater inflow was examined, according to the phenomena of groundwater mixing, groundwater flow and groundwater chemistry. The study region is composed of different aquifer systems; including karst-fracture media (Rattga-Jeed carbonates aquifer), fissure–porous media (Mullusi, Mullusi-Ubaid, Hartha-Rutba, and Digma-Tayarat aquifers) and porous media (Permo-carboniferous clastics rocks of Ga’ra aquifer).The aquifers are vertically super-imposed or of lateral contacts make open hydraulic connection between aquifers system. There is a severe shortage of water resources in the region because of rare precipitation and strong evapotranspiration. These conditions have hampered eco-environm
... Show MoreIn this paper, we propose a new approach of regularization for the left censored data (Tobit). Specifically, we propose a new Bayesian group Bridge for left-censored regression ( BGBRLC). We developed a new Bayesian hierarchical model and we suggest a new Gibbs sampler for posterior sampling. The results show that the new approach performs very well compared to some existing approaches.
Iraq suffers from serious pollution with harmful particles that have important direct and indirect effects on human activities and human health. In this research, a system for detecting pollutants in the air was designed and manufactured using infrared laser technology. This system was used to detect the presence of pollutants in the dust storms that swept the city of Baghdad which could have a negative impact on human health and living organisms.
The designed detection system based on the use of infrared laser (IR) with a wavelength of 1064 nm was used for the purposes of detecting pollutants based on the scattering of the laser beam from these pollutants. The system was aligned to obtain the best signal for the scattered rays, w
... Show MoreThe research aims to identify the effect of using the strategy of Roundhouse on the achievement of fourth-grade students of computer and their Attitudes towards it. The research sample consisted of (61) fourth-grade secondary school students distributed into the experimental group consisted of (31) students study computer according to the Roundhouse strategy, and the control group consisted of (30) students follow the traditional method. The researcher designed an achievement test consisting of (30) items of multiple choice. To measure the attitudes of students towards the computer, a questionnaire of (32) paragraphs with three alternatives was designed by the researcher. The results showed that there is a statistically significant diffe
... Show MoreThe study of vegetative change of cities is one of the most important studies related to human life because of its direct correlation with the temporal conditions that occur. These include the economic problems that force people to move and look for job opportunities in the city, which leads to an increase in the population density of cities, especially for cities with an important economic and administrative location as in the capital city of Baghdad. In this study, the effect of the increasing in population density was analyzed on the urban planning of Baghdad city. The decreasing in vegetation was due to the increasing of urban areas on the outskirts of the city, which led to an increase in its area. Moreover, urban cities increased t
... Show MoreBaghdad University Radio Telescope (BURT) is a 3 meter radio telescope that was installed in the main campus of the University of Baghdad in Jadiriyah. Radio telescopes, in general, offer a wide range of applications in radio astronomy, which are usually used to detect the neutral hydrogen emission line at a wavelength of 21 cm. One of the key applications of BURT is to observe the Milky Way galaxy and to determine its rotation curve. However, performing such observations requires accurate determination of the appropriate observing time as well as the coordinates. This paper focuses on how the observing time and coordinates are calculated correctly and accurately. The horizontal coordinate that corresponds to the galactic coor
... Show MoreReservoir fluids properties are very important in reservoir engineering computations such as material balance calculations, well testing analyses, reserve estimates, and numerical reservoir simulations. Isothermal oil compressibility is required in fluid flow problems, extension of fluid properties from values at the bubble point pressure to higher pressures of interest and in material balance calculations (Ramey, Spivey, and McCain). Isothermal oil compressibility is a measure of the fractional change in volume as pressure is changed at constant temperature (McCain). The most accurate method for determining the Isothermal oil compressibility is a laboratory PVT analysis; however, the evaluation of exploratory wells often require an esti
... Show MoreHaemoproteus burhinus is described from the stone curlew, Burhinus oedicnemus saharae (Reichenow) from Al-Attariya, 45 km SE Baghdad city middle of Iraq. It is related to but differs from H. peireci in that it hypertrophied the erythrocyte and the erythrocyte nucleus is always laterally displaced in microgametocytes.