Background: Nanoparticles are clusters of atoms in a size range from (1-100) nm. Nano dentistry creates amazing useful structures from individual atoms or molecules (nanoparticles), which provides a new alternative and a possibly superior strategy in prevention and treatment of dental caries through management of dental plaque biofilms. The aim of the study was to test the sensitivity of Streptococcus mutans to different concentrations of hydroxyapatite and iron oxide nanoparticles suspension solutions, in comparison to chlorhexidine, and de-ionized water, in vitro. Materials and methods: Agar well technique was applied to test the sensitivity of Streptococcus mutans to different concentrations of hydroxyapatite and iron oxide nanoparticles compared with chlorhexidine 0.2% as a control positive and de-ionized water as control negative. Zone of inhibitions which is clear zone of no growth of the bacteria were measured across the diameter of each well, no zone indicated a complete resistance of bacteria to the agents. Results: Values of mean of inhibition zone for all concentrations of hydroxyapatite nanoparticles were zero. While for iron oxide nanoparticles, they were zero until reaching the last three concentrations, in which there was a respective increase with a highly significant difference between groups (p>0.01). When making multiple comparisons of the inhibition zones of iron oxide nanoparticles between groups, findings showed that the inhibition zones of 17%, 20% and 22.5% of iron oxide nanoparticles were more than all other concentrations that had no inhibition zones with a significant difference (p>0.05). There was a highly significant difference between each concentration of hydroxyapatite and iron oxide nanoparticles with chlorhexidine and de-ionized water (p>0.01). Conclusion: Streptococcus mutans were not sensitive to hydroxyapatite nanoparticles, as there was a complete resistance for the agent. While for iron oxide nanoparticles, Streptococcus mutans were sensitive to 17.5%, 20% and 22.5% and sensitivity increased with the increase in concentration with a statistically highly significant difference and this indicates an antibacterial activity of this material. Keywords: Hydroxyapatite nanoparticles, Iron oxide nanoparticles, streptococcus mutans, Inhibition zone. (J Bagh Coll Dentistry 2018; 30(1): 69-75)
Background: Poly (methyl methacrylate) has been widely utilized for fabrication of dentures for many years as it has good advantages but not achieved all demands of the mechanical properties such as low transverse strength, low impact strength, low surface hardness, high water solubility and high water sorption. Material and method: To provide bonding between ZrO2 nanoparticles and PMMA matrix, the ZrO2 Nano-fillers were surface-treated with a saline coupling agent. Plasma surface treatment of polyethylene (PE) fiber was done to change surface fiber by using DC- glow discharge system. For characterization of interring any functional groups, the (FTIR) spectrum were done .then the mechanical properties studied to choose the appropriate perc
... Show MoreThe official spokesperson considered responsible for the transmission of information and communication messages that convey the government’s view on the various political and economic issues that affect the public opinion towards the performance achieved by the various governmental institutions and for the purpose of communicating with the media in a positive and effective manner, a number of institutions in the world in general and in Iraq in particular have nominated a spokesman to coordinate the efforts and the dissemination of news and the preparation of press conferences to contribute to the achievement of a positive and effective level between the government and the media, so this study has tackled to deal with the credibility of
... Show MoreThis study sought to determine the impact of spreading the culture of quality in improving the quality of tourism service in some hotels in Erbil governorate. The theme of excellence in providing service and attention to it has become the concern of most organizations in general and tourism service organizations in particular. Tourists try to establish the mental status of customers about their tourism organizations had to pay attention to the quality of service provided to the customer and work to develop them to the advanced stages of satisfaction and happiness of customers and this will certainly positively affect the improvement of service in the tourism sector, Of the research variables were examined statistically by distrib
... Show MoreAbstract: Recombinant Newcastle disease virus (rNDV) has shown an anticancer effect in preclinical studies, but has never been tested in a lung cancer models. In this study we explored the anticancer activity of genetically modified NDV expressing IL-2-P53 (rClone30–IL-2-P53) in lung cancer model. We have cloned IL-2 and P53 genes and inserted them in the viral genome of New Castle Disease Virus to create a genetically modified rNDV- IL-2-P53 virus and tested the anti-tumor activity of the new virus in vitro on different types of cancer cell lines by MTT assay. TheIL-2 and P53 gene were successfully cloned and inserted into the viral genome by using a Mlu I and Sfi I endonucleases, viral vector was constructed correctly and successf
... Show MoreCoupling reaction of m-and p- amino acetop henone and p-amino benzoic acid with (LHistidine) gave the new bidentate azo ligands (L1, L2 and L3). The prepared ligands were identified by FT-IR, UV-Vis, 1HNMR and GC- mass sp ectroscopic technique. Treatment of the prepared ligands with the following metal ions (CoII, NiII, CuII, ZnII, CdII and HgII) in aqueous ethanol with a 1:2 M:L ratio and at optimum pH, yielded a series of neutral complexes of the general formula [M (L)2 Cl2]. The prepared complexes were characterized by using flame atomic absorption, FT-IR, UV-Vis and 1HNMR spectroscopic methods as well as magnetic susceptibility and conductivity measurements. Chloride ion content was also evaluated by (Mohr method). The nature of the com
... Show MoreThe research endeavors to harness the benefits stemming from the integration of constraint theory into construction project management, with the primary goal of mitigating project completion delays. Additionally, it employs fuzzy analysis to determine the relative significance of fundamental constraints within projects by assigning them appropriate weights. The research problem primarily revolves around two key issues. Firstly, the persistent utilization of outdated methodologies and a heavy reliance on workforce experience without embracing modern computerized technologies. Secondly, the recurring problem of project delivery delays. Construction projects typically encompass five fundamental constraint types: cost restrictions, tim
... Show MoreAntibiotic resistance is the capability of the strains to resist or protect themselves from the effects of an antibiotic. Such a resistance towards the current antimicrobials leads to the search of novel antimicrobials. Nanotechnology has been promising in different field of science and among it is the use of nanoparticles as antibacterial agents. The gastrointestinal tract seems to be the primary reservoir of uropathogenic E.coli (UPEC) in humans. UPEC strains harbour the urinary tract and cause urinary tract infection. They cause serious ailments in terms of humans. They develop resistance and increase their virulence by forming biofilms. They also show a remarkable locomotory movement with the aid of autoinducer controlled ge
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