Background: Irrigation of the canal system permits removal of residual tissue in the canal anatomy that cannot be reached by instrumentation of the main canals so the aim of this study was to compare and evaluate the efficiency of conventional irrigation system, endoactivator sonic irrigation system,P5 Newtron Satelec passive ultrasonic irrigation and Endovac irrigation system in removing of dentin debris at three levels of root canals and to compare the percentage of dentin debris among the three levels for each irrigation system. Materials and methods: Forty extracted premolars with approximately straight single root canals were randomly distributed into 4 tested groups of 10 teeth each. All canals were prepared with Protaper Universal hand files to size #F4, and irrigated with 2.5% NaOCI 1 ml between files and 5ml for 60 seconds as a final irrigant by different irrigation devices; group one, by using conventional system; group two, by using Endoactivator sonic irrigation system, group three, by using Satelec Passive Ultrasonic irrigation and group four by using the Endovac system. After the final irrigation, the roots were split longitudinally and photographed with a digital microscope. The roots were magnified to 100X; a percentage of debris was calculated for the apical 0-3, middle 3-6 and coronal 6-9 mm. The debris score was calculated as a percentage of the total area of the canal that contained debris as determined by pixels in Adobe PhotoshopCS5. Data were analyzed statistically by ANOVA and LSD at 5% significant level. Results: when comparing the debris remaining, the Endovac, Endoactivator and Satelec groups showed significantly less debris than the conventional group at all three levels (p < 0.01). The Endovac group showed significantly less debris than the Endoactivator group at middle and coronal levels while no significant difference found between the Endovac system and Endoactivator system at apical level. The apical 0-3 mm showed significantly more debris than both the middle and coronal level for all groups. Conclusion: The EndoVac system showed a higher cleaning capacity of the canal at all levels, followed by the protocols that used Endoactivator sonic irrigation system. The conventional irrigation system with maxi-i-probe needles showed inferior results. The apical three millimeters showed a greater amount of debris than the 3-9 millimetres from the working length, regardless of the irrigation device used.
Thin filis have been prepared from the tin disulphide (SnS2 ), the pure and the doped with copper (SnS2:Cu) with a percentages (1,2,3,4)% by using ahemical spray pyrolysis techniqee on substrate of glass heated up to(603K)and sith thicknesses (0.7±0.02)?m ,after that the films were treated thermally with a low pressure (10-3mb) and at a temperature of (473K) for one hour. The influence of both doping with copper and the thermal treatment on some of the physical characteristics of the prepared films(structural and optical) was studied. The X-ray analysis showed that the prepared films were polycrystalline Hexagonal type. The optical study that included the absorptance and transmitance spectra in the weavelength range (300-900)nm
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Several new derivatives of 1, 2, 4-triazoles linked to phthalimide moiety were synthesized through following multisteps. The first step involved preparation of 2, 2-diphthalimidyl ethanoic acid [2] via reaction of two moles of phthalimide with dichloroacetic acid. Treatment of the resulted imide with ethanol in the second step afforded 2, 2-diphthalimidyl ester [3] which inturn was introduced in reaction with hydrazine hydrate in the third step, producing the corresponding hydrazide derivative [4]. The synthesized hydazide was introduced in different synthetic paths including treatment with carbon disulfide in alkaline solution then with hydrazine hydrate to afford the new 1, 2, 4-triazole [10]. Reaction of compound [10] with different alde
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Air pollution evaluation of the operational processes in the East Baghdad oil field was carried out. The analysis was carried out by ICP-MS technique. Total Suspended Particles (TSP) air load was higher than Iraqi Standards and world international allowable limits of World Health Organization. The mean concentrations of gases carbon monoxide, carbon dioxide, sulfur dioxide, in the air were within national and world standards, while the mean concentration of nitrogen dioxide was higher than standard limits. The air of the study area is considered a good quality for CO, CO2 and NO2 with no health effect, while it is hazardous for TSP that have serious risk for people with respiratory disease. The mean concentrations of Cd, Cr, Cu and
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The negative impact of oral diseases on the function, economy, and general health of the population is well‐documented. In the last decades, evidence linking increased expression of depression and oral diseases/conditions has significantly increased. The aim of this study is to assess the association between oral disease/conditions and self‐reported symptoms of depression individuals.
A specially designed questionnaire was distributed via social media for 1 week. It consisted of two main sections; the first section was dedicated to collect demographic variables and self‐reported symptoms
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Condensation of 1,2- dibromo ethane with para hydroxy benzoic acid gave 1,2-Ethane-bis- 4-oxybenzoic [1]. This Compound was converted with the thionyl chloride to give 1,2-Ethane-bis- 4-oxybenzoyl chloride [2]. Reaction of compound [2] with thiosemicarbizades gave 1,2-Ethanebis[4-oxybenzoyl-thiosemicarbazide] [3] and opteined 1,2-Ethane-bis[3-mercapto-5-phenoxy- 1,2,4-triazole] [4] from treatment compound [3] with NaOH (4%) .The new compounds 1,2- Ethane-bis[3-(substituted thioacyl)-4-(substituted acyl)-5 phenoxy-1,2,4-triazole] [5a-d] and 1,2- Ethane-bis[3-(substituted alkylthio)-5 phenoxy-1,2,4-trizole] [5e-f] derived from compound [4] were synthesized and characterized by physical and spectral data. All the compounds [4], [5a-d] and [5e-
... Show MoreThe present study deals with the application of an a bundant low cost biosorbent sunflower shell for metal ions removal. Lead, Cadmium and Zinc were chosen as model sorbates. The influences of initial pH, sorbent dosage, contact time, temperature and initial metal ions concentration on the removal efficiency were examined. The single ion equilibrium sorption data were fitted to the non-competitive Langmuir and Freundlich isotherm models. The Freundlich model represents the equilibrium data better than the Langmuir model. In single, binary and ternary component systems,Pb+2 ions was the most favorable component rather than Cd+2 and Zn+2 ions. The biosorption kinetics for the three metal ions followed the p
... Show MoreThis paper presents a grey model GM(1,1) of the first rank and a variable one and is the basis of the grey system theory , This research dealt properties of grey model and a set of methods to estimate parameters of the grey model GM(1,1) is the least square Method (LS) , weighted least square method (WLS), total least square method (TLS) and gradient descent method (DS). These methods were compared based on two types of standards: Mean square error (MSE), mean absolute percentage error (MAPE), and after comparison using simulation the best method was applied to real data represented by the rate of consumption of the two types of oils a Heavy fuel (HFO) and diesel fuel (D.O) and has been applied several tests to
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