Background: This study compared in vitro the marginal adaptation of three different, low shrink, direct posterior composites Filtek™ P60 (packable composite), Filtek™ P90 (Silorane-based composite) and Sonic fill™ (nanohybrid composite) at three different composite/enamel interface regions (occlusal, proximal and gingival regions) of a standardized Class II MO cavity after thermal changes and mechanical load cycling by scanning electron microscopy. Materials and methods:Thirty six sound human maxillary first premolars of approximately comparable sizes were divided into three main groups of (12 teeth) in each according to the type of restorative material that was used: group (A) the teeth were restored with Filtek™ P60 and single bond™ Universal adhesive using horizontal incremental technique, group (B)the teeth were restored with Filtek™ P90 and P90 system adhesive using horizontal incremental technique and group (C) the teeth were restored with Sonic fill™ composite and single bond™ Universal adhesive using bulk technique.After specimens were stored in distilled water at 37°C for 7 days, all specimens were subjected to thermocycling at (5° to 55 °C), then submitted to mechanical load cycling (intermittent axial force of 49N and a total of 50.000 cycles). The specimens were observed under scanning electron microscope at (2000 X) to measure marginal gap width (the distance between the dental wall and the restoration) at occlusal, proximal and gingival regions in micrometer using Tescan software, version 3.5. Data were analyzed statistically by one way ANOVA test and least significant difference tests. Results:The results showed that the silorane-based posterior composite (Filtek™ P90) showed significantly the least marginal gap width at the occlusal, proximal and gingival regions after the application of thermal changes and mechanical load cycling in comparison to the two methacrylate-based posterior composite Filtek™ P60 (packable) and the Sonic fill™ (nano-hybrid). Sonic fill™ bulk fill composite that relied on the vibration concept to lower the viscosity of high filler loaded composite material showed significantly lesser marginal gaps width at occlusal, proximal and gingival composite/enamel interface regions in comparison with Filtek™ P60 (packable composite) using horizontal incremental technique. The silorane-based composite (Filtek™ P90) showed non-significant difference in marginal gaps width at the three different regions. While, both methacrylate based Filtek™ P60 and Sonic fill™ composite showed significantly lesser marginal gap width at the occlusal region in comparison with gingival regions. Conclusion: None of the low-shrinkage composite restorative materials tested in this study totally prevented micro-gap formation at composite/enamel interfaces of Class II MO cavity.
Background: 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 MoreIt is clear that correct application of antibiotic prophylaxis can reduce the incidence of infection resulting from the bacterial inoculation in a variety of clinical situations; it cannot prevent all infections any more than it can eliminate all established infections. Optimum antibiotic prophylaxis depends on: rational selection of the drug(s), adequate concentrations of the drug in the tissues that are at risk, and attention to timing of administration. Moreover, the risk of infection in some situations does not outweigh the risks which attend the administration of even the safest antibiotic drug. The aim of this study was to comp
... Show MoreAcquisition provisions in Islamic jurisprudence
It is clear that correct application of antibiotic prophylaxis can reduce the incidence of infection resulting from the bacterial inoculation in a variety of clinical situations; it cannot prevent all infections any more than it can eliminate all established infections. Optimum antibiotic prophylaxis depends on: rational selection of the drug(s), adequate concentrations of the drug in the tissues that are at risk, and attention to timing of administration. Moreover, the risk of
... Show MoreThe objective of this research is to identify the effect of Using Fryer strategy on achievement and systemic thinking in the subject of chemistry of second class intermediate school students. The sample of research consisted of 59 students in one intermediate school in Baghdad/Iraq, split into two groups; experimental and control. The scientific material of the study is related to Chapters II and III of the Science Book for the second Intermediate School for the Year (2019-2020). The scientific test is composed of 25 test items whilst the second instrument for research related to systematic thinking test consisted of 12 items. The results of the research showed that the use of Fryer's chemistry-teaching strategy has increased achievement an
... Show MoreThe objective of this research is to identify the effect of Using Fryer strategy on achievement and systemic thinking in the subject of chemistry of second class intermediate school students. The sample of research consisted of 59 students in one intermediate school in Baghdad/Iraq, split into two groups; experimental and control. The scientific material of the study is related to Chapters II and III of the Science Book for the second Intermediate School for the Year (2019-2020). The scientific test is composed of 25 test items whilst the second instrument for research related to systematic thinking test consisted of 12 items. The results of the research showed that the use of Fryer's chemistry-teaching strategy has increased achieve
... Show MoreStable new derivative (L) Bis[O,O-2,3;O,O-5,6(carboxylic methyliden)]L-ascorbic acid was synthesized in good yield by the reaction of L-ascorbic acid with dichloroacetic acid with ratio (1:2) in presence of potassium hydroxide. The new (L) was characterized by 1H,13C-NMR, elemental analysis (C,H) and Fourier Transform Infrared (FTIR). The complexes of the ligand (L) with metal ion, M+2= (Cu, Co, Ni, Cd and Hg) were synthesized and characterized by FTIR, UV-Visible, Molar conductance, Atomic absorption and the Molar ratio. The analysis evidence showed the binding of the metal ions with (L) through bicarboxylato group manner resulting in six-coordinated metal ion.
Some feline intestinal parasites such as Toxocara, Giardia, and Cryptosporidium can spread to humans through feces. Therefore, it is important to prevent exposure of family members by screening cat fecal samples twice per year for potential treatment regimes. This study was initiated to compare and identify gastrointestinal parasites of domestic and stray cats (Felis domesticus) in Baghdad City, Iraq. Parasite eggs and oocysts were identified under light microscopy by applying standard laboratory techniques (flotation and sedimentation). Overall, 59 of 121 (48.7%) fecal samples were positive for intestinal parasites. The rate of infection by Toxoplasma gondii was (3.31%), Isospora spp. (6.61%), Cryptosporidium spp. (31.4%), and Toxocara spp
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