Background: The bond strength of root canal sealers to dentin was important for maintaining the integrity of the seal in root canal filling in both static and dynamic situations. In a static situation, it should eliminate any space that allowed the percolation of fluids between the filling and the wall while in a dynamic situation; it was needed to resist dislodgement of the filling during subsequent manipulation. Materials and Methods: Forty mandibular premolars were selected for this study. All canals were instrumented using ProTaper rotary instruments. Instrumentation was done with copious irrigation of 5.25% sodium hypochlorite. Roots were randomly divided into four groups according to the type of cleaning and method of root canal irrigation (ten teeth for each group): Group A. The root canals were irrigated with 5 ml of 17% of EDTA for 1 minute and 5 ml of 5.25% NaOCl. Group B. Cleaning with waterlase laser. Group C. The root canals were irrigated with 5 ml of 5mg/ml of siwak (Salvadora persica) extract for one minute. Group D. The root canals were irrigated with 5 ml of 5% of green tea (camellia sinensis) extract for one minute. All groups were rinsed with distilled water and then obturated with cold lateral condensation technique and i Root sp sealer (Bioceramic sealer, the roots then stored in moist environment at 37°C for one week. Three horizontal sections were prepared at a thickness of 1 mm ±0.1 in the apical, middle and coronal parts of each root. The test specimens were subjected to the push-out test method using a Universal Test Machine that carried 1-mm, 0.5- mm and 0.3-mm plungers for coronal, middle and apical specimens, respectively. The loading speed was 0.5 mm/ min. The computer showed 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: In all groups the mean value of push-out strength was greatest in apical area and least in coronal area and the middle area was in between, except in Waterlase the middle area showed the least mean push-out strength. Conclusion: Herbal extracts used in this study (Siwak and green tea) can be used safely as an intra-canal irrigant for smear layer removal with efficiency that is comparable with conventional synthetic materials (EDTA) and more complicated methods (Waterlase).
The reaction paths of the C-C and C-H bond cleavage in the anthracene and phenanthrene aromatic molecules are studied by applying the ab-initio DFT method. It is found that the C-C bond cleavage proceeds via a singlet aromatic transition state, compelled through a disrotatoric ring opening reaction. A suprafacial H atom shift follows the transition state, leading to the formation of a methylene -CH2 and an acetylenic or allenic moiety. The calculated activation energies for anthracene range from 158.81-208.90 kcal/mol and the reaction energies from 96.106-156.976 kcal/mol. For phenanthrene, the energy values are 157.39-202.34 kcal/mol and 62.639-182.423 kcal/mol, respectively. For the C-H cleavage reactions, the calculated reaction energies
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Superconducting thin films of Bi1.6Pb0.4Sr2Ca2Cu2.2Zn0.8O10 system were prepared by depositing the film onto silicon (111) substrate by pulsed laser deposition. Annealing treatment and superconducting properties were investigated by XRD and four probe resistivity measurement. The analysis reveals the evolution of the minor phase of the films 2212 phase to 2223 phase, when the film was annealed at 820 °C. Also the films have superconducting behavior with transition temperature ≥90K.
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The aim of present study to investigate the effect of Coraindrum sativum leaves extract on reproductive activity of male albino mice .Thirty male mice with age of 80-100 day and weight between 25-30 g were divided into three groups: group 1 (untreated), group 2 and 3 were administrated orally for 30 days with aqueous extract of Coraindrum sativum leaves at dose 125 and 250mg/kg.b.w. respectively. The following parameters were evaluated: serum testosterone levels, testes weights, sperm characteristics [motility, viability, spermatozoa, morphology and concentration] and histology changes of the testis. The results showed that the treatment caused highly significant degrease (P<0.01) in testosterone levels and the weight of testes assoc
... Show MoreIn digital images, protecting sensitive visual information against unauthorized access is considered a critical issue; robust encryption methods are the best solution to preserve such information. This paper introduces a model designed to enhance the performance of the Tiny Encryption Algorithm (TEA) in encrypting images. Two approaches have been suggested for the image cipher process as a preprocessing step before applying the Tiny Encryption Algorithm (TEA). The step mentioned earlier aims to de-correlate and weaken adjacent pixel values as a preparation process before the encryption process. The first approach suggests an Affine transformation for image encryption at two layers, utilizing two different key sets for each layer. Th
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This study presents, for the first time, an innovative Jet Plasma-assisted technique for the green synthesis of TiO₂@Ag core–shell nanoparticles using chard leaf extract as a natural reducing and stabilizing agent. The Jet Plasma provides a highly energetic environment that accelerates nucleation and core–shell formation at low temperatures without toxic precursors. The synthesized nanoparticles exhibited uniform and stable structures, as confirmed by comprehensive characterization techniques including X-ray diffraction (XRD), Fourier-transform infrared spectroscopy (FTIR), ultraviolet–visible (UV–Vis) spectroscopy, transmission electron microscopy (TEM), and zeta potential analysis. XRD patterns confirmed the crystalline anatase
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Abstract: The aim of this study is to assess the effectiveness of 940 nm diode laser in comparison to Endoactivator in elimination of smear layer in terms of radicular dentin permeability and ultra-structural changes of root canal walls by SEM evaluation. Twenty-eight single-rooted extracted lower premolars were instrumented up to size X4 (protaper Next, Dentsaply) and divided into two experimental groups according to the irrigation system, G1; activated by EndoActivator and G2; activated by Diode laser 940 nm, CW mode, 1.7 W. Afterward, the roots were made externally impermeable, filled with 2%methylene blue dye, divided horizontally into three segments representing the apical, middle, and coronal thirds then examined under stereo- micr
... Show MoreBackground: Hypothyroidism is a decrease in the production of the thyroid hormones and leads to gland dysfunction. Ashwagandha extract was used as an ayurvedic treatment and supposed to be as antihypothyroidism agent.
Objectives: to investigate the impact of ashwagandha (Ash) extract on propylthiouracil (PTU)-induced hypothyroidism in rats.
Subjects and Methods: The rats were divided into three groups, control group, PTU (hypothyroid) group (6mg/kg/day by oral route), PTU (6mg/kg/day by oral route) +Ash (50mg/kg/day by oral route) treated group. All treatment continued for
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The present research included synthesis of silver nanoparticle from(1*10-3,1*10-4 and1*10-5) M aqueous AgNO3 solution through the extract of M.parviflora reducing agent. In the process of synthesizing silver nanoparticles we detected a rapid reduction of silver ions leading to the formation of stable crystalline silver nanoparticles in the solution.
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Anastatica hierochuntica L. is distributed throughout Arabain Peninsula, and elsewhere it is locally called "Kuffe Maryam" .All parts of the plant are used in folk medicine. This study amid to investigate the effect of aqueous extract of anastatica hierochunctica L. on the cancer cell lines AMN-3. Anti cancer activity of aqueous extract of anastatica hierochunctica L. showed anticancer activity against AMN-3 cell line for twelve concentrations (0.04, 0.09, 0.195, 0.39, 0.78, 1.56, 3.125, 6.25, 12.5, 25, 50, 100) mg/mL in comparison with negative control.