Background: This study aimed to compare the surface microhardness (MH) and mineral content of white spot lesions(WSLs) after using bioactive glass (BAG)casein phosphopep-tides-amorphous calcium phosphate(CPP-ACP),and nanohydroxyapatite(Nano-HAP) under pHcycling. Material and method:18 sound maxillary first premolar were used for the study.10 were selected for the vickers microhardness test, For Energy-dispersive X-ray spectroscopy analysis (EDX), the remaining 8 premolar teeth were used, 40 sections of enamel blocks (Four from each tooth) were produced from the middle part of the buccal and palatal surfaces of teeth for MH test while 48 sections of enamel blocks (Six from each tooth) were produced for EDX analysis. Enamel slabs were divided into four groups: control group that preserved in DDW, Nano-HAP, CPP-ACP and BAG group, then were demineralised using 0.1 M lactic acid and 8 wt.% carboxymethylcellulose gel to create artificial WSL. The speci-mens were subjected to a pH cycling regime for 20 days. The remineralisation potential of the specimens was studied by evaluating the surface MH, calcium (Ca), and phosphrous (P) at different stages: baseline, after production of WSLs, and after treatment with different ma-terials. The gathered data were statistically analyzed using repeated measures one-way ANOVA test and the Bonferroni test. Results: The results showed that Nano-HAP had the highest mean values of MH (157.699 kg/ mm2), Ca (50.108), and P (24.840) followed by BAG (MH=147.769 kg/ mm2, Ca=47.408, P=22.285), and the lowest mean value was found in the control group (MH=52.299 kg/ mm2, Ca=35.291, P=17.228). Bonferroni’s and Tukey's HSD test showed higher significant difference (p<0.05) from demineralization to remineralization phase in all groups, except when compared control group with WSL (Demineralization) showed non-significant difference (P>0.05). Conclusion:all tested agents have highly signif-icant remineralizing potential. Nano-HAP has the highest potential for remineralizing initial enamel caries lesions
Vitrifications process one of the important methods to immobilize nuclear waste. In this research nuclear waste (Strontium Oxides) with molecular weight (5%) was immobilized by vitrification methods in two types of borosilicate glass (c-type) which are glass and glass-ceramics. To investigate the physical, chemical and mechanical properties of glass and glass-ceramic after immobilize nuclear waste these samples irradiated by gamma ray radiation. Co-60 was used as gamma a irradiation with dose rate 0.38 kGy/hr for different period of time. It’s found that gamma radiation affected the glass and glass-ceramic properties. From phase analysis by the x-ray diffraction for glass-ceramic samples proved that at doses 343kGy change the cry
... Show MoreThe issue, the existence of God Almighty, and the creativity of the universes including the whale, and assets and how diversified, and faith in him and his lordship and divinity, is a delicate issue, and very important and dangerous, and it occupied human thought old and new, and still occupy it until God takes the land and on it. Many complex issues of thought, behavior, and ethics have resulted in the belief of many communities in the existence of the Almighty, having ruled their minds, depicting their beliefs and distancing their thoughts about slippage and abuse. When they looked at the wonders of creatures and the minutes of the assets, they thought about the planetary and astronomical motion systems. His existence was denied by ath
... Show MoreThe Impact of Intellectual trends on the nature of the Economic Structure of Iraq
Abstract
The changes that happened in the environment of business have great effects upon organizations with different activities specially the banks which requires the existence of an able opinion resources can adapt with the changes . Accordingly importance put upon intellectual capital which become one of the basic resources for organizations and one of success and growth elements with the availability of expertise , skills and capability of making essential changes in different process due to the presentation of innovations and creations of the to support banks activities .Therefore the intellectual capital represents the more r
... Show MoreThis research is to take advantage of the performance capabilities which the piano has become famous with and transfer the impact of that advantage to the possibilities of playing the violin. The research aims to introduce the effect of using the piano on the development of the violinists' musical potential. The research, in its literature, focuses on the interpretation of the impact on the possibility of both instruments (piano and violin) in two main sections: the piano (its origin, potential and role in music) and the violin (its origin, potential and role in music). The procedures of the research consisted of presenting a special analysis of a questionnaire consisting of a number of questions presented by the researcher to her resear
... Show MoreBackground: Recently increasing number of people are using mouthwashes for general and oral care while the primary appeal of a mouthwash is an aid to breath freshness and cleansing the mouth, the majority of mouthwashes also claim to have antiseptic properties. The aim of this study is to determine the antimicrobial effectiveness of eight types of mouthwashes against Streptococcus mutans, Staphylococcus aureus and Candida albicans in vitro. Materials and methods: Agar diffusion technique was used to evaluate the antimicrobial activity of eight types of mouthwashes against Streptococcus mutans, Staphylococcus aureus and Candida albicans isolated from the oral cavities of patients attending dental clinics at college of dentistry - Baghdad Uni
... Show MoreThis study is concerned with making comparison in using different geostatistical methods for porosity distribution of upper shale member - Zubair formation in Luhais oil field which was chosen to study.
Kriging, Gaussian random function simulation and sequential Gaussian simulation geostatistical methods were adopted in this study. After preparing all needed data which are contour map, well heads of 12 wells, well tops and porosity from CPI log. Petrel software 2009 was used for porosity distribution of mentioned formation in methods that are showed above. Comparisons were made among these three methods in order to choose the best one, the comparing cri
Nine new compounds of 2-amino-5-chlorobenzothiazole derivatives were synthesized. These new compounds were formed through the reaction of 2-amino-5-chlorobenzothiazole 1 with ethyl chloroacetate and KOH, which gave an ester derivative 2, followed by refluxing compound 2 with hydrazine hydrate to afford hydrazide derivative 3. The reaction of compound 3 with CS2 and KOH gave 1,3,4-oxadiazole-2-thiol derivative 4, and then the reaction of compound 2 with thiosemicarbazide to produce compound 5 then treated it with 4%NaOH led to ring closure to provide 1,2,4-triazole-3-thiol derivative
... Show MorePoly methyl methacrylate PMMA polymer could be considered the main material that used mostly in the recent years in denture base fabrication. It commonly known by it is poor strength properties such as low impact strength. The aim of the present research was to enhance the performance of PMMA denture base through the addition of two kind of nanoparticles (nano particles that selected from artificial and natural sources). Nano -particles from both Al2O3 and crushed peanut Peel were used for comparing purposes.Various weight fraction used in this study for both kinds of the additive (1%, 2% and 3%). Moreover, in this work a study and evaluation in impact strength (I.S.) value were done before and after immersion. The new prepared nanocompo
... Show MoreInternational trade in services is becoming increasingly important as it is an economic activity that deals with invisible trade, which has become increasingly important in the balance of international trade. The establishment of the WTO is a starting point in international trade relations. It is responsible for all aspects of international trade, , And in view of the continued increase in international trade in services, the need for more internationally recognized rules has become more urgent, especially as it has been increasingly proven that the traditional framework of public services is inadequate to operate some of the most dynamic and innovative sectors of the economy. (GATS) to be the regulatory framework for this sector
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