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.
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In this study Isolated Pathogenic bacteria which causes Tonsillitis in Children with ages between 3-17 years. They are admitted to Central Children Hospital (Al-Karch) and Ebn-Albalady Hospital (Al-Rusafa). 200 cases were collected which include 120 Male and 80 Female. The result of the recent study shows that the isolation percentage was 40% from Male and 35% from Female. In this study Fifty six isolated were Identified, 20 were ?-hemolytic Streptococcus which was Streptococcus pyogenes, formed (36%) from all isolated.6 Pathogenic bacteria were ?- hemolytic Streptococcus which was Streptococcus pneumoniae formed (11%). The number of Moraxella catarrhalis bacteria was 12 formed (21%), the number of Haemophilus influenzae was 1
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This study has been carried out in the Station of Poultry Researches which is affiliated to the General Office of Agricultural Researches / Ministry of Agriculture during the period from 01/04/2018 to 14/05/2018 there are 300 one day old chick of type (Ross 308) used in this study, and has been fed on diets which green tea powder (Camellia sinensis) has been added to it with the levels 0.5 , 1 , 1.5 , 2 g/kg as a feed for the treatments T 2 , T 3 , T 4 and T 5 respectively and compared to the control treatment T 1 which is devoid of addition, every treatment included three replicates each one has 20 birds in order to study the effect of adding a various levels of green tea powder (Camellia sinensis) to the diet on the productive performance
... Show MoreThis study deals with free convection heat transfer for the outer surface of two
cylinders of the shape of (Triangular & Rectangular fined cylinders with 8-fins),
putted into two different spaces; small one with dimension of (Length=1.2m,
height=1m, width=0.9m) and large one with dimension of (Length=3.6m, height =3m,
width=2.7m). The experimental work was conducted with air as a heat transport
medium. These cylinders were fixed at different slope angles (0o, 30o, 60o and 90o)
.The heat fluxes were (279, 1012, 1958, 3005, 4419) W/m2, where heat transferred by
convection and radiation. In large space, the results show that the heat transfer from
the triangular finned cylinder is maximum at a slope angle equals
The study highlighted the transformation of value systems and educational patterns between past and present, especially with the introduction of modern variables and means, such as mobile phones, the internet, social media, and others. These factors have contributed both positively and negatively to the study. The study highlights the integral role of the school in collaboration with the family in guiding and educating children. It also emphasizes the active role of the school in developing students' abilities and skills, either attracting them to school or vice versa. This includes an examination of the essential skills required in education and their role in achieving a state of psychological well-being and systematically developing child
... Show MoreIn this work, effects of using different evaporative cooling pads (ECPs) on the energetic and exergetic efficiency of a direct evaporative air cooler (DEAC) have been theoretically and experimentally investigated. Three types of ECPs were used, i.e., honeycomb cellulose cooler pad (HCCP), shading-cloth cooler pad (SCCP), and aspen wood wool cooler pad (AWWCP). For SCCP and AWWCP, a 3-cm pad thickness was used, while for the HCCP, three different values of pad thickness were used, i.e., 3, 5, and 7 cm. Tests were carried out using air velocities of 8, 14, and 19 m/s, measured at the DEAC outlet. Engineering equation solver (EES) used for performing the required calculations of the various parameters affecting the thermal performance of the D
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ABSTRACT Porous silicon has been produced in this work by photochemical etching process (PC). The irradiation has been achieved using ordinary light source (150250 W) power and (875 nm) wavelength. The influence of various irradiation times and HF concentration on porosity of PSi material was investigated by depending on gravimetric measurements. The I-V and C-V characteristics for CdS/PSi structure have been investigated in this work too.
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