Background: to evaluate the effect of different dentifrices on the surface roughness of two composite resins (nanofilled-based and nanoceramic – based composite resins). Materials and methods: Forty specimens (diameter 12 mm and height of 2mm) prepared from different composite resin materials: Z350 (nanofilled composite, and Ceram-X (nanoceramic) .they were subjected to brushing simulation equivalent to the period of 1 year. The groups assessed were a control group brushed with distilled water (G1), Opalescence whitening toothpasteR (G2), Colgate sensitive pro-relief (G3) and Biomed Charcoal Toothpaste (G4). The initial and final roughness of each group was tested by surface roughness tester. The results were statistically analyzed using
... Show MoreAbstract: An unfavorable complication of root canal is vertical root fracture. The aim of present study is to evaluate the vertical root fracture of treated teeth filled with gutta percha and Resilon obturating material using different sealers. Forty mandibular premolars used in the study. Canals randomly divided into four groups (n=10). Group-A eugenol-based (Endofill) sealer with gutta percha; GroupB epoxy-amine (AH Plus) sealer with gutta percha; Group-C resin-based (Real Seal) sealer with Resilon; or Group-D epoxide-based (Perma Evolution) sealer with gutta percha. Roots mounted vertically in cold cure acrylic blocks and subjected to vertical loading with a crosshead speed of 1mm ̸min. The point at which fracture of the roots occurred
... Show MoreThe objective of the research , is to shed light on the most important treatment of the problem of missing values of time series data and its influence in simple linear regression. This research deals with the effect of the missing values in independent variable only. This was carried out by proposing missing value from time series data which is complete originally and testing the influence of the missing value on simple regression analysis of data of an experiment related with the effect of the quantity of consumed ration on broilers weight for 15 weeks. The results showed that the missing value had not a significant effect as the estimated model after missing value was consistent and significant statistically. The results also
... Show MoreOne of the most popular causes for implant infection is dental plaque bacteria. Previous studies have shown the bactericidal effect of CO2 laser irradiation on bacteria associated with soft tissue surrounding the implant materials. No published studies have examined the effect of irradiation by CO2 laser on Streptococcus oralis and Staphylococcus aureus.The aim of this study was to evaluate the bactericidal effect of CO2 laser on bacteria that are causing dental implant infections. This study was carried out on two isolates of bacterial species out of 25 samples, isolated from patients having soft tissue infections around the dental implant. These two pure isolates including Streptococcus oralis and Staphylococcus aureus were identified
... Show MoreRicinus communis L. is an important medical plant hence it contains many active compounds. The aim of this research is to study the effect of plant growth regulators on callus induction and Rutin concentration. A combination of Benzyle adenine (BA) and Indol Acetic acid (IAA) at (0.0,1.0,2.0) mg/L was added to the media, the highest fresh weight of the induced callus from stem explant was (4.97) gr . at (1.0,1.0) mg/L BA and IAA consenquently the same combination gave the highest dry weight of callus (0.42) gr. while the combination at (2.0,1.0) mg/L BA and IAA gave the highest fresh weight of induced callus from Leaves explant (5.28) gr., then (2.0,1.0) mg/L BA and IAA gave the highest dry weight for callus induced from leaves at (0.55
... Show MoreBackground: the oral cavity is consider to be an open ecosystem, with the balance between the microorganism’s entrance and the defenses of the host. The initiation of periodontitis has been associated with restricted kinds of anaerobic bacteria, such as Aggregatibacter actinomycetemcomitans (A.a) and Porphyromonas gingivalis (P.g) in plaque subgingivally. Ozone has a biological effects on bacteria due to oxidation of bio-molecules and its toxins. The aim is to determine and compare the antimicrobial effect of gaseous ozone and ozonized water on the growth of isolated anaerobic bacteria (A.a and P.g) when exposed to different time intervals. Materials and methods:This experiment is done byozone generator OLYMPIC- III(600mg/hr) to gene
... Show MoreThis study was conducted at the poultry farm of the Department of Animal Production/College of Agriculture/University of Baghdad/Abu Ghraib, on 252 birds (180 females and 72 males). This study aims to observe the effect of melatonin implantation and exposure to different light colors and their interaction on characteristics of fertility and hatching of local Iraqi chickens. The birds were divided into three sections (white, red and green) each section contains two lines, one of which has been planted melatonin under the skin of the neck of birds and the other has not been planted hormones. The results showed that melatonin implantation and exposure to different light colors did not significantly affect the hatching rate of fertilized eggs a
... Show MoreThis research is carried out to study the effect of the external post-tensioning technique on the flexural capacity of simply supported composite castellated beam experimentally. In this research, seven composite castellated beams having the same dimensions and material properties were cast and tested up to failure by applied two concentrated loads at 700 mm from each end. Two external strands of 12.7 mm diameter were fixed at each side of the web of strengthening beams and located at depth 180 mm from top fiber of the section (dps) at each end of the beam. The strands have been tensioned by using a hydraulic jack with a constant stress of 100 MPa. This research aims to study the effect of the strengthening by different shapes of st
... Show More
