Aim: surface modification of titanium using fiber laser 1064 nm to enhance the bond strength to resin cement. Material and Methods: thirty titanium discs of 0.6 cm x 0.3 cm (diameter and thickness respectively) were categorized after preparation into three groups (n=10) as follows: control group with no surface treatment and two test groups were treated with fiber laser after estimation the appropriate parameters in the pilot study which are 81 ns pulse duration, 30,000 Hz frequency, 50 µm spot size and 10,000 mm/s scanning speed and different average power values (10 W and 20 W) depending on the tested group. Titanium discs surface characterization was performed by scanning electron microscope (SEM), and surface roughness tester. Following these tests, resin cement application to titanium discs was performed. Shear bond strength (SBS) values were determined by universal testing machine. ANOVA and Tukey HSD tests were used for analyzing of data (α = 0.05).Results: Higher average surface roughness (Ra) value was observed in (10 W) group followed by (20 W) group and the lowest surface roughness value was in the control group, additionally lowest SBS value was obtained from the control group and the highest SBS value was obtained from (20 W) group followed by (10 W) group. Conclusion: bond strength between titanium and resin cement can be significantly enhanced by using fiber laser as a surface treatment. Average power of fiber laser is essential parameter in enhancing the roughness of titanium surface and bonding to resin cement.
Recently, dental implants have experienced increasing demand as one of the most effective, permanent and stable ways for replacing missing teeth. However, peri-implant diseases that are multispecies plaque-based infections may ultimately lead to implant failure (i.e., late peri-implantitis). Therefore, the present study aims to detect the microbial diversity of subgingival plaque in peri-implantitis cases (N = 30) by comparing with healthy implants (N = 34) using culture-based identification methods, including VITEK 2 system. An increase in microbial diversity (29 species along with 1 and 7 isolates, which were classified as a genus and unidentified species, respectively) were observed in subgingival sites of diseased implants dominated by
... Show MoreThe effect of subinhibitory concentration of Antibiotics on the Adherence of S.aureus (Coagulase Positive Staphylococci), and S.epidermidis (Coagulase negative Staphylococci) and Pseudomonas aeruginosa, Enterobacter cloacae, Citobacter freundi (Gram negative bacteria) was done and the results revealed that Rifampicin was the best antibiotic inhibiting Staphylococci adherence and Vancomycin has less effect on the adherence of Staphylococci, whereas Tetracyclin was the best antibiotic inhbiting Gram negative bacteria adherence and Amikacin has the lest less effect on inhibiting bacterial adherence.
This research was to determine the effect of rare earth metal (REM) on the as-cast microstructure of Mg-4Al alloy. The rare earth metal used here is Lanthanum to produce Mg-4Al-1.5La alloy. The microstructure was characterized by optical microscopy. The phases of this alloy were identified by X-ray diffraction. The microstructure of Mg-4Al consists of α-Mg and grain boundaries with precipitated phase particles. With the addition of Lanthanum, three distinct phases were identified in the X-ray diffraction patterns of the as cast Mg-4Al-1.5La: Mg, Al11La3, Al4La. The Mg17Al12 phase was not detected. The addition of Lanthanium increases the hardness and dec
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The aim of the research is to determine the impact of the Iraqi public budget on IPSASs by conducting the questionnaire; the research was based on the hypothesis that "there is an impact of the adoption of the International Accounting Standards in the general budget of Iraq”. The research concluded that the government accounting system closely interferes with the general budget at all stages. The shifting towards the accrual basis is the first element of the reform package towards reaching the reform of the state budget. Without reforming government accounting, it is almost impossible to develop the budget. IPSASs are a recognized reference to the assessment and development of governmen
... Show Morethe study aimed to identify the impact of the types of cooking utensils in transition metal elements to food and the effect of acid and storage in the concentration of these elements. used five types of cooking utensils including aluminum. tefal, astainls steel, glass. (pyrex), and ceramic prepared in it the food meal. the same meals were repeated add to them acid. the estimate of mineral elements in the meal prepared before storage and after storage in refrigerator temperature degree. the result shows the increase of aluminum concentration in the meals that prepared in aluminum pot reaching 2.913 pmm while reached less concentration in the meal prepared in astainls pot reaching 0.325 pmm. the highest concentration of iron reached 25.2 p
... Show MoreIn this contribution, density functional theory-based calculations have been carried out to assess the electronic, photocatalytic and optical properties of Ce1-xTixO2 system. Ti incorporation leads to a decrease of Ce 4f states and enhancement of Ti 3d states in the bottom of conduction band. Furthermore, it was found that doping ceria with Ti-like transition metals could evidently shift the absorption of pure CeO2 towards higher wavelength range. These findings can provide some new insights for designing CeO2-based photocatalysts with high photocatalytic performance. To the best of our knowledge, this investigation calculates Mullikan’s charge transfer of Ce1-xTixO2 system for the first time. Charge transfer reveals an ionic bond between
... Show MoreIn this paper fractional Maxwell fluid equation has been solved. The solution is in the Mettag-Leffler form. For the corresponding solutions for ordinary Maxwell fluid are obtained as limiting case of general solutions. Finally, the effects of different parameters on the velocity and shear stress profile are analyzed through plotting the velocity and shear stress profile.
The objective of the research is to identify the effect of an instructional design according to the active learning modelsالباحثين in the achievement of the students of the fifth grade, the instructional design was constructed according to the active learning models for the design of education. The research experience was applied for a full academic year (the first & the second term of 2017-2018). The sample consisted of 58 students, 28 students for the experimental group and 30 students for the control group. The experimental design was adopted with partial and post-test, the final achievement test consisted of (50) objectives and essays items on two terms, the validity of the test was verified by the adoption of the Kudoric
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