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)
In recent years, there has been growing interest in using Nanosystems in different biomedical applications. Among all metal nanoparticles, selenium nanoparticles have attracted the attention of many researchers due to its low toxicity and nutritional supplementation value. The purpose of the current study was designed to examine the possible effect of selenium nanoparticles in combination with fenugreek leaves extract (an edible herb with good medicinal properties) in the treatment of oxidative stress status-related to polycystic ovary syndrome in letrozole-induced PCOS (an imbalance of reproductive hormones that causes infertility) in adult female rats. Cold plasma was used in the preparation of selenium nanoparticles subsequently the prod
... Show MoreCerebellum is the most important and critical part of the central nervous system, cerebellum is very sensitive to the abnormal changes during the embryological development in its histological structure, the exposure to any infection during embryogenesis produce abnormalities in the cerebellum and behavioral of offspring. In this study we tried to study the ontogenesis of the cerebellum in the embryos of the albino rats and detection the effect of the AgNPs on the ontogenesis of the rat cerebellum after exposure of AgNPs during pregnancy. we used 60 female pregnant rats divided in to three group, each contain 20 female, (G1) treated with 2mg/kg /day suspension of silver nanoparticles (Ag NPs) (G2) treated with 20mg/kg/day AgNPs from first da
... Show MoreThe Corrosion protection effectiveness of Alimina(Al2O3,50nm)and Zinc oxide (ZnO,30nm) nanoparticales were studied on carbon steel and 316 stainless steel alloys in saline water (3.5%NaCl)at four temperatures: (20,30,40,50 OC)using three electrodes potentiostat. An average corrosion protection efficiencies of 65 %and 80% was achieved using Al2O3 NP's on carbon steel and stainless steel samples respectively, and it seems that no effect of rising temperature on the performances of the coated layers. While ZnO NP'S showed protection efficiency around 65% for the two alloys and little effected by temperature rising on the performanes of the coated layers. The morphology of the coated spesiemses was examined by Atomic force microscope.
A modified chemical method was used to prepare titanium dioxide nanoparticles (TiO2 NPs), which were diagnosed by several techniques: X-ray diffraction, Fourier transform infrared, field emission scaning electron microscopy, energy disperse X-ray, and UV-visible spectroscopy, which proved the success of the preparation process at the nanoscale level. Where the titanium oxide particles have an average particle size equal to 6.8 nm, titanium dioxide particles were used in the process of adsorption of Congo red dye from its aqueous solutions using a batch system. The titanium oxide particles gave an adsorption efficiency of Congo red dye up to more than 79 %. The experimental data of the adsorption process were analyzed with kinetic models and
... Show MoreMetal and metal oxide NPs have shown to be perfectly synthesized by using plant extracts with high efficiency, low cost and low toxicity. Our goal was to synthesize ZnO NPs by using an extract of pomegranate seeds and investigate the anticorrosion, antimicrobial and antioxidant properties of the synthesized ZnO NPs. The results have shown that the use of pomegranate in the green synthesis of ZnO NPs gave a good yield, with a low cost and non-toxic approach. The electrophoretic deposition (EPD) was used to coat stainless steel (S.S) by synthesized ZnO NPs in an alcoholic solution at room temperature producing a good coating against corrosion. The corrosion properties were investigated in a saline solution and a temperature range of (293–32
... Show MoreBackground: The fracture of instruments within root canal during endodontic treatment is a common incidence, fracture because of fatigue through flexure occurs due to metal fatigue, this study aimed to assess the effect of curvature angle and rotational speed on the cyclic fatigue of different type of Endodontic NiTi Rotary Instruments and compare among them. Materials and method: Three types of rotary instruments with tip size 0.25: ProTaPer F2 (Densply, Malifier) Revo-S SU( 0.06 taper, MicroMega) and RaCe system (0.06 taper, FKG, Dentaire), Forty file of each instrument were used within two canals with angle of curvature (40 &60 )at two speed (250&400)RPM, twelve group were formed for all instruments(total number=120),ten file fo
... Show MoreTo explore the durability of some local species of wood to fungal deterioration among the
storage period, this research has conducted on three species Eufcalyptus cammaldulensis,
Juglans regia, presence of some genus of fungi; Aspergillus, Penicillium,Botryoderma,
Chaetomium, Phoma, Cladosporium and Pacilomyces in different intensities.
The two fungi Aspergillus and Penicillium appeared more dominants than others, therefore
they were chosen for the pathogenicity test. The results showed that the two species of fungi
preferred Juglans wood firstly were the size of infection was more than 10 times of any of the
other two woods. Eucalyptus showed similar response to that of Morus, but with Aspergillus
it was few bett
Darcy-Weisbach (D-W) is a typical resistance equation in pressured flow; however, some academics and engineers prefer Hazen-Williams (H-W) for assessing water distribution networks. The main difference is that the (D-W) friction factor changes with the Reynolds number, while the (H-W) coefficient is a constant value for a certain material. This study uses WaterGEMS CONNECT Edition update 1 to find an empirical relation between the (H-W) and (H-W) equations for two 400 mm and 500 mm pipe systems. The hydraulic model was done, and two scenarios were applied by changing the (H-W) coefficient to show the difference in results of head loss. The results showed a strong relationship between both equations with correlation coefficients of 0.999,
... Show MoreThis study included the isolation and diagnosis of Pseudomonas aeruginosa from cases of burns samples. 100 samples were collected from resident patients at Al-Kindi Teaching Hospital, who suffer from different types of burns. Pseudomonas aeruginosa was isolated and diagnosed with 39% of the total samples. The cold and hot aqueous and alcoholic extract of flaxseeds oil was prepared and its inhibitory efficacy has been studied on the growth of isolated Pseudomonas aeruginosa. It is revealed that both extracts of flaxseeds oil had a high inhibitory effect on Pseudomonas aeruginosa growth. The Minimum Inhibitory Concentration (MIC) of flaxseed oil on the studied bacteria was also estimated, which was 25 mg/ml. In conclusion, the efficacy of fla
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