Background: The aim of this study was to evaluate the push-out bond strength of four different obturation materials to intraradicular dentin and to determine the failure mode. Materials and method: forty straight palatal roots of the maxillary first molars teeth were used in this study, the roots were instrumented using crown down technique and rotary EndoSequence system, the roots were randomly divided into four groups according to the materials used for obturation (n=10).Group (1): AH Plus sealer and gutta-percha. Group (2): Activ GP glass ionomer sealer and Activ GP gutta-percha (Activ GP system). Group (3): Bioceramic sealer and Bioceramic gutta-percha. Group (4): GuttaFlow2 sealer and gutta-percha. For all groups single cone obturation technique was used. After incubation period of one week, the roots were embedded in clear acrylic resin and each root sectioned into three levels apical, middle and cervical. The bond strength was measured using computerized universal testing machine, each section fixed in the machine so that the load applied from apical to coronal direction at 0.5mm/min speed and the computer drew curve to show the higher bond force before dislodgment of the filling material. After de-bonding each sample was examined under Stereomicroscopic and the type of failure mode was recorded. Results: showed a non significant difference between AH plus group and Bioceramic group. AH Plus group showed a very highly significant difference with Activ GP group and a highly significant difference with GuttaFlow2 group. There were significant differences between coronal level and both apical and middle levels with no significant differences between apical and middle levels within each group. Conclusion: AH plus group showed the highest mean of bond strength in comparing to other tested groups
In this work, the total linear attenuation coefficients µ(cm
-1
) were calculated and studied
for particulate reinforced polymer-based composites. Unsaturated polyester (UP) resin was
used as a matrix filled with different concentrations of Al, Fe, and Pb metal powders as
reinforcements. The effect of the metal powders addition at different weight percentages in
the range of (10,20,30,40,50)wt % and gamma energy on attenuation coefficients was studied.
The results show, as the metallic particulates content increase, the attenuation coefficients will
increase too, while it, were exhibited a decrease in their values when the gamma energy
increase.The total linear attenuation coefficients of gamma ray fo
Digital Elevation Model (DEM) is one of the developed techniques for relief representation. The definition of a DEM construction is the modeling technique of earth surface from existing data. DEM plays a role as one of the fundamental information requirement that has been generally utilized in GIS data structures. The main aim of this research is to present a methodology for assessing DEMs generation methods. The DEMs data will be extracted from open source data e.g. Google Earth. The tested data will be compared with data produced from formal institutions such as General Directorate of Surveying. The study area has been chosen in south of Iraq (Al-Gharraf / Dhi Qar governorate. The methods of DEMs creation are kri
... Show MoreThe applications of Multilevel Converter (MLC) are increased because of the huge demand for clean power; especially these types of converters are compatible with the renewable energy sources. In addition, these new types of converters have the capability of high voltage and high power operation. A Nine-level converter in three modes of implementation; Diode Clamped-MLC (DC-MLC), Capacitor Clamped-MLC (CC-MLC), and the Modular Structured-MLC (MS-MLC) are analyzed and simulated in this paper. Various types of Multicarrier Modulation Techniques (MMTs) (Level shifted (LS), and Phase shifted (PS)) are used for operating the proposed Nine level - MLCs. Matlab/Simulink environment is used for the simulation, extracting, and ana
... Show MoreIn this paper, we made comparison among different parametric ,nonparametric and semiparametric estimators for partial linear regression model users parametric represented by ols and nonparametric methods represented by cubic smoothing spline estimator and Nadaraya-Watson estimator, we study three nonparametric regression models and samples sizes n=40,60,100,variances used σ2=0.5,1,1.5 the results for the first model show that N.W estimator for partial linear regression model(PLM) is the best followed the cubic smoothing spline estimator for (PLM),and the results of the second and the third model show that the best estimator is C.S.S.followed by N.W estimator for (PLM) ,the
... Show MoreTo study the site of placentae and the umbilical artery blood flow of different age groupsand relate that to the newborn baby and the mother. 117 placentae samples were investigatedusing ultrasound and 30 placentae samples were studied using Doppler ultrasound during theperiod from August 2007 to August 2008 for full term placentae of mothers aged 15- > 45 yearsold. By ultrasound; there was detection of good pe rcentage of the placental site to be on theposterior wall of the uterus in case of male babies, while it was anterior in case of female babiesand it was previa and fundal in females more than in the males. The Doppler ultrasound revealedthat the mother in any age group can conceive and have a healthy placenta because the readings ina
... Show MoreA total of 41 patients with gastro duodenal symptoms (show signs of inflammation with or without duodenal ulcer) . 21 males (51.2%) and 20 female (48.8%) with an average age 0f (20 – 80) years old under going gastrointestinal endoscopy at Baghdad teaching hospital in internal disease clinical laboratory , between (February – June) 2009 . Biopsies specimen of antrum , gastric fundus ,& duodenal bulb were examined by the following methods (rapid urease test , Giemsa stain section to detect bacteria , & Haematoxilin and Eosin stained section for pathological study which are considered the gold standard methods , sera or plasma from these patients were tested by immunochromotography (ICM),serological m
... Show MoreBackground: Dental implant is one of the most important options for teeth replacement. In two stage implant surgery, a few options could be used for uncovering implants, scalpel and laser are both considered as effective methods for this purpose. The Aim of the study: To compare soft tissue laser and scalpel for exposing implant in 2nd stage surgery in terms of the need for anesthesia, duration of procedure and pain level assessment at day 1 and day 7 post operatively using visual analogue scale . Materials and methods: Ten patients who received bilateral implants participated after healing period completed, gingival depth over each implant was recorded and then implant(s) were exposed by either scalpel or laser with determination for th
... Show MoreThe adult worms of the Microphallidae family are mainly found as intestinal parasites of birds and mammals, while metacercariae is most commonly found in decapodal crustaceans. The Microphallidaeare family is spread throughout the world. It includes approximately 47 genera. Mature worms usually enter the digestive system of vertebrates, especially birds and mammals. Microphallidae contain eight subfamilies: Androcotylinae - Basantisiinae - Endocotylinae - Gynaecotylinae - Levinseniellinae - MaritrematinaeMicrophallinae - Sphairiotrematinae. Therefore, due to the lack of studies on the Microphallidae family in Iraq, we began to develop a database on this important family.
Purpose: To validate a UV-visible spectrophotometric technique for evaluating niclosamide (NIC) concentration in different media across various values of pH. Methods: NIC was investigated using a UV-visible spectrophotometer in acidic buffer solution (ABS) of pH 1.2, deionized water (DW), and phosphate buffer solution (PBS), pH 7.4. The characterization of NIC was done with differential scanning calorimeter (DSC), powder X-ray diffraction (XRD), and Fourier transform infrared spectroscopy (FTIR). The UV analysis was validated for accuracy, precision, linearity, and robustness. Results: The DSC spectra showed a single endothermic peak at 228.43 °C (corresponding to the melting point of NIC), while XRD and FTIR analysis confirmed the identit
... Show MoreEthanol as a solvent, a precursor of titanium isopropoxide and a stabilizer of either hydrochloric acid or ammonium hydroxide was used to prepare a titanium dioxide aqueous solution. The aqueous solutions with different values of pH and the morphology of the resultant reaction of the nanoparticles of titanium dioxide were investigated. The X-ray diffraction showed that at low temperatures and with acidic solutions, rutile structures are more favorable to grow on titanium dioxide synthesized, while at low and average temperatures and with base solutions, anatase phase is more pronounced. The crystalline form and the re-confirmation of the crystallite size growth were observed by the scanning electron microscopy. The atomic force micr
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