Background: One of the major problems in endodontics is micro-leakage of root canal fillings which might contribute to the failure of endodontic treatment. To avoid this problem, a variety of sealers have been tested. The objective of this, in vitro, study was to evaluate the shear bond strength of four resin based sealers (AH plus, silver free AH26, RealSeal SE and Perma Evolution permanent root canal filling material) to dentin. Materials and Methods: Forty non-carious extracted lower premolars were used. The 2mm of the occlusal surfaces of teeth were sectioned, to expose the dentin surface. The exposed dentin surfaces of teeth were washed with 5ml of 2.5% NaOCl solution followed by 5ml of 17 % EDTA then rinsed by deionized water to remove the smear layer. The teeth were divided into four groups according to the type of sealer used: Group A: silver free AH26, Group B: AH plus., Group C: RealSeal SE, Group D: Perma Evolution. Polyethylene tube cylinders (4mm internal diameter & 5mm length) were fixed on the dentin surfaces. Then freshly mixed sealers were poured into the tubes and allowed to bench set for two hours and were stored at 100% humidity and 37?C for one week. With an Instron machine, the shear bond strength between the tested sealers and the dentin, in Mpa, was measured. Statistical analysis was carried out using the one-way ANOVA and Student’s t-tests. Results: Perma Evolution scored the highest mean value of sheer bond strength, being 3.343 Mpa followed by the AH plus (2.786 Mpa) and AH26 (2.149 Mpa). While the RealSeal scored the lowest mean value of sheer bond strength, which was (1.831 Mpa). ANOVA test results showed a highly statistically significant difference. Student's t test results revealed significant differences between all the compared groups, except one paired group had a non-significant difference in the shear bond strength which was between the AH plus and Perma Evolution groups (P>0.05). Conclusions: The results of this study pointed to Perma Evolution which scored the highest sheer bond strength between the tested sealers.
The research deals with the concept of rationalization of consumption, which is legitimately legitimized, by indicating the permissibility of consumption and its limits in Islam, the legitimate aspects of spending and its controls, and the concept of development in the Islamic economy. The researcher followed the descriptive method by presenting the legal texts and jurisprudential opinions and linking them to contemporary economic problems.The research has reached several conclusions, the most important of which is that the goal of Islam in relation to consumption is to inform the Muslim of the amount of economic maturity, and the truth of alms is good in money and religion. It is necessary for achieving maturity that both means
... Show Morebjective researcher through this research to Put a theoretical framework to strategic orientation the center on the market in the business and the diagnosis and interpretation of the nature of the link between relationships and influencing strategic orientation dimensions Almtmthelh organizations (Entrepreneurial Orientation, market Orientation, Interaction Orientation) and the performance of the Iraqi Private Banks The research community and the level of dimensional and through the use of scale (Balanced Scorecard) Bmnzawradtha the four, the test of this research in the Iraqi banking sector (Gulf Commercial Bank
... Show MoreShear lag is the phenomenon that occurs when a supported slender member undergoes deformation from lateral loading, causing in-plane non-uniform distribution of stresses that results in reducing the member’s minimum strength capacity. This paper investigates the behaviour of shear distribution in steel I-section and box girders when subjected to both static and impact loadings. Three-dimensional finite element analysis models were prepared in Strand7 and validated against experimental results providing a basis for further comparison research into shear lagging effects. A parametric study was conducted comparing the effects of impact loading through certain specified velocities at the midspan of restrained ends. It provided new ins
... Show MoreThe corrosion behavior of low carbon steel in washing water of crude oil solution has been studied potentiostatically at five temperatures in the range (30–70)°C .The corrosion potential shifted to more negative values with increasing temperature and the corrosion current density increased with increasing temperature. Folic acid had on inhibiting effect on the corrosion of low carbon steel in washing water at a concentration (5× 10-4-- 5× 10-3 ) mol/dm3 over the temperature range (30–70)°C. Values of the protection efficiency were calculated from the corrosion current density .From the general results for this study, it can be seen that thermodynamic and kinetic function were also calculated (?G, ?S, ?H and Ea )
... Show MoreThis research is drawn from a doctoral dissertation, studying the approach of Sheikh Abd al-Qadir al-Muhajir al-Sanandji al-Kurdi (1303 AH) on the issue of proving the existence of God Almighty.
Sheikh Abd al-Qadir al-Sanandji was one of the scholars well versed in mental sciences. He has many books, all of them in the sciences of speech and wisdom, and among his books is the book (Raising the Eyebrow in Explanation of Ithbat al-Wajib), which is still a manuscript that has not been printed.
Through this book, the researcher studied the evidence of Sheikh Abdul Qadir to prove the existence of God Almighty, and compared it with the evidence of philosophers and theologians.
At the beginning, he presented a study on the import
Problem Statement: Despite the critical role of arm movement in freestyle swimming, many learners— specially female students at Baghdad University's College of Physical Education and Sport Sciences— face difficulties executing the pushing phase of the stroke correctly. This phase essential for generating propulsion and maintaining body coordination in water. Traditional teaching methods lack immediate feedback on the quality and force of arm movements, impeding effective motor learning and coordination. Approach: the researchers developed a custom-made device designed to measure the pressure force exerted by the palms during freestyle swimming. The device features pressure sensors attached both hands, a processor that analyzes the colle
... Show MoreBy reading the book (Endless Forms Most Beautiful: The New Science of Evo Devo) by Sean B. Carroll, new horizons opened up about the nature of the formation of the living organism. Although he presented the idea that the artist was influenced by the material assets of nature in his holographic art formations, the new science of Evo-Devo (Evolutionary Developmental Science) provided models worth standing on when comparing the similarity of the formation of living organisms on the one hand, and the formation of works of art with holographic organic bodies on the other. But the excitement lies in the fact that the formation of living natural organisms is often driven by subtle intelligent mechanisms that are different from the mechanisms us
... Show MoreCongenital distal vaginal obstruction is usually asymptomatic in a newborn female. On rare occasions, it may present as an acute emergency with life threatening complications.This paper is reporting the rare condition of two newborn females presenting urgently with abdominal distension and acute urinary retention as a result of congenital distal vaginal Obstruction. The case history and urgent management shall be presented and both conditions shall be discussed.
Mishrif Formation is the main reservoir in oil-fields (North Rumaila, South Rumaila, Majnoon, Zubair and West Qurna) which located at Basrah southern Iraq. The Inductively coupled plasma-Mass spectrometer (ICP-MS) was used for the water chemistry analysis and Scanning Electron Microprobe (SEM) for the purpose of mineralogy diagnosis. A weak acidic water of salinity six-time greater than seawater plays a role in generating the formation pressure and controlling the fluid flow. The potentiometric subsurface maps were modeled and the direction of super-pressure sites that are of a great importance in the oil exploration were marked to pay attention during future drilling.