Background: The bond strength of the root canal sealers to dentin seems to be a very important property for maintaining the integrity and the seal of root canal filling. The aim of this study was to evaluate the shear bond strength of four different obturation systems using push-out test. Materials and methods: Forty straight palatal roots of the maxillary first molars teeth were used in this study, these roots were instrumented using crown down technique and ProTaper system, instrumentation were done with copious irrigation of 2.5% sodium hypochlorite and 17% buffered solution of EDTA was used as final irrigant followed by distilled water, roots were randomly divided into four groups according to the obturation system (ten teeth for each group): Group I: AH26 sealer and lateral condensation technique, Group II: AH26 sealer and single cone obturation technique, Group III: AH26 sealer and thermafil obturation technique and Group IV: RealSeal SE sealer and lateral condensation technique, the roots then stored in moist environment at 37°C for one week The roots were embedded in clear acrylic resin and each root sectioned into three levels apical, middle and cervical. The measurement of each section was taken to prepare the supporting jig for the sections and the punch used in pushout test, the bond strength was measured using computerized universal testing machine each section fixed in the machine so that the load applied from apical to cervical direction at 0.5mm/min. speed and the computer drew curve to show the higher bond force before dislodgment of the filling material. These forces were divided by the surface area to obtain the bond strength in MPa. Results: Statistical analysis was performed and the result showed avery highly significant differences between the four obturation systems at each level and there were non significant differences between all level apical, middle and cervical within each obturation system except a significant difference found between cervical and apical level in single cone obturation system. Conclusion: This study showed that the shear bond strength of AH26 sealer was higher than RealSeal SE sealer when the same obturation technique was used. The shear bond strength was affected by the obturation technique and lateral condensation technique showed higher bond strength than thermafil and single cone obturation technique when the same type of sealer was used and the bond strength was not or little affected by the tooth level
The size and the concentration of the gold nanoparticles (GNPs)
synthesized in double distilled deionized water (DDDW) have been
found to be affected by the laser energy and the number of pulses.
The absorption spectra of the nanoparticles DDDW, and the
surface plasmon resonance (SPR) peaks were measured, and found to
be located between (509 and 524)nm using the UV- Vis
spectrophotometer. SPR calculations, images of transmission
electron microscope, and dynamic light scattering (DLS) method
were used to determine the size of GNPs, which found to be ranged
between (3.5 and 27) nm. The concentrations of GNPs in colloidal
solutions found to be ranged between (37 and 142) ppm, and
measured by atomic absorptio
(1)
This study aims to derive a sustainable human development index for the Arab countries by using the principal components analysis, which can help in reducing the number of data in the case of multiple variables. This can be relied upon in the interpretation and tracking sustainable human development in the Arab countries in the view of the multiplicity of sustainable human development indicators and its huge data, beside the heterogeneity of countries in a range of characteristics associated with indicators of sustainable human development such as area, population, and economic activity. The study attempted to use the available data to the selected Arab countries for the recent years. This study concluded that a single inde
... Show More
The present study aimed to investigate the histological, enzyme histochemical changes and liver function effects of Maxxthor insecticide on albino rats in liver. The experiment included 20 rat which were divided into four groups, the first group 5 rats were considered the control animals and the others were divided equally into three groups with a dose of 0.01, 0.1and 1 mg / kg of body weight, respectively for a period 40 days. The animals given each 48 hours via oral route Maxxthor by tube dosage after dissolved with distilled water. Microscopic examination of liver showed inflammatory cell aggregation around vessels, congestion and dilation of sinusoids hepatocytes hypertrophy with severs inflammatory cells infiltration, kupffer cells pro
... Show More
(1)
Taguchi experimental design (TED) is applied to find the optimum effectiveness of aqueous Red Pomegranate Peel (RPP) extract as a green inhibitor for the corrosion of mild steel in 2M H3PO4 solution. The Taguchi methodology has been used to study the effects of changing, temperature, RPP concentration and contact period, at three levels. Weight-loss measurements were designed by construction a L9 orthogonal arrangement of experiments. Results of the efficiencies of inhibition were embraced for the signal to noise proportion & investigation of variance (ANOVA). The results were further processed with a MINITAB-17 software package to find the optimal condition
... Show MoreInflammatory bowel disease (IBD) is a common chronic inflammatory disease of the gastrointestinal tract, including ulcerative colitis and Crohn's disease. ulcerative colitis (UC) disease is characterized by chronic, persistent, recurrent, and nonspecific intestinal ulcers and mucosal inflammation. This study investigated the protective effects of cinnamic acid on dextran sodium sulfate (DSS) induced ulcerative colitis in mice. Forty adult male mice were collected and randomly divided into five groups, group Ӏ received a suspension of distill water and poloxamer, and group ӀӀ received 3% DSS in drinking water for 7 consecutive days. Two treatment groups received an oral suspension of cinnamic acid 50 and 25 mg/kg respectively an
... Show More
(4)
(4)
(12)
(15)
This study was conducted to estimate the extent of damage to the population in Basra, southern Iraq, specifically the areas adjacent to the Shatt al-Arab and the Arabian Gulf, which are the Al-Fao district and the Al-Siba region. They are affected by the progression of saline water resulting from the lack of water imports and the Karun River interruption, which led to high concentrations of salts in the Shatt Al-Arabs. Consequently, its effect on lands and all life types in these areas requires correcting a map of the study area to drop the groundwater sites as well as calculate the total dissolved salts, electrical conductivity and pH. This study concluded that the groundwater contains very high percentages of total dissolved solid
... Show More
Communication skills are essential for health professionals to achieve a positive relationship with patients, improving their health and quality of life. Communication is the foundation for obtaining medical history and conveying a diagnosis and treatment plan.
To assess the knowledge, practice of communication skills among primary care physicians, to find out any barriers related to the communication skills, and the association between the studied variables with knowledge and practice of communicati
This paper presents an experimental and theoretical analysis to investigate the two-phase flow boiling heat transfer coefficient and pressure drop of the refrigerant R-134a in the evaporator test section of the refrigeration system under different operating conditions. The test conditions considered are, for heat flux (13.7-36.6) kW/m2, mass flux (52-105) kg/m2.s, vapor quality (0.2-1) and saturation temperature (-15 to -3.7) ˚C. Experiments were carried out using a test rig for a 310W capacity refrigeration system, which is designed and constructed in the current work. Investigating of the experimental results has revealed that, the enhancement in local heat trans
... Show More
(3)
The objective of this research is to measure the training programs and identify the nature and then measure how it reflected on the quality of municipal services provided by the municipal departments investigated by measuring the quality of services based on quality standards, the researcher chose four municipal departments in the Rusafa / Baghdad (164 people) representing the directors and their assistants, officials of the municipal departments, the people and the engineering staff in charge of the task forces as well, including the survey of the views of the concerned persons in the management of the Vocational Training Institute in the Secretariat of the Republic, The quality of the municipal services
... Show More