Background: The accuracy of fitness of any dental casting is imperative for the success of any prosthodontic treatment. From the time that dental casting was first introduced, efforts have been made to produce more accurate and better fitted castings with minimal marginal discrepancy. The aim of this in vitro study was to evaluate the effects of three different investing and burnout techniques on the vertical marginal discrepancies ofceramometalcopings invested with two types of phosphate- bonded investments. Materials and methods: Sixty wax patterns were fabricated on a standardized prepared brass die representing an upper central incisor by the aid of a custom-made split mold. Three different investing and burnout techniques were applied for an Iraqi investment and a commercial type; Group I:Ring investing with conventional burnout technique (RC);Group II: Ringless investing with conventional burnout technique (RLC);Group III: Ring investing with accelerated burnout technique (RA).Twenty wax patterns of each group were divided into two subgroups according to the type of investment material used (10 for each subgroup) represented as (B) for the BellaStar XL and (W) for the WYMvest investments. Complete castings were finished and seated on the metal die. The accuracy of fit of each coping was determined by measuring the vertical marginal discrepancies between the finish line on the metal die and the margins of each coping at four specific reference points on the labial, mesial, palatal, and distal aspects of the die by the aid of a light microscope supplied with a digital camera.The arithmetic mean of each three records was computed and regarded as the amount of the marginal discrepancy of each coping and was used as a unit for the statistical analysis. Results: Mean marginal accuracy for W(RLC)was found to be the least (13.839+4.5724 um) while the highest mean value related to B(RLC) (29.033+2.102 um). In general, ANOVA test showed significant results among the mean values of the Binvestment subgroups while LSD test showed non-significance between the (RA) and both the (RC) and (RLC) subgroups. On the other hand, significance was present between the (RLC) and (RA)of the Winvestment subgroups while non-significance was located between the (RC) and both the (RLC) and (RA) subgroups. Comparing similar subgroups of the two tested investments, the Student's t-test showed non-significance between the (RC) subgroups while high significance was located between the (RLC) and (RA) subgroups respectively.Concerning the vertical marginal discrepancy of the copings, applying the (RC) technique for both investments caused non-statistical significance between the labial, mesial, palatal, and distal aspects.The (RLC) technique caused high significance between the four aspects, while the (RA) technique caused non-significance between the labial aspect only and the others. Conclusion: The Iraqi investment generally produced less vertical marginal discrepancies (using the three different investing and burn-out techniques) than the commercial investment.In order to achieve a better marginal fit, it seems that ceramometalcopings invested with the commercial investment tested are better be cast using the conventional ring investing and burnout technique.
The process of self-assessment plays a key role in achieving quality educational institutions (college, department or program academic particular), because the assessment process provides reviews of the effectiveness of the criteria used in the enterprise, especially in the field of teaching and learning, and is result self-assessment providing self-assessment report. The self- assessment can be performed at different levels (college, academic department, Master, Ph.D. program, or courses). The importance of the research focused on to provide a measure of self-assessment helps profile officials in the implementation of the assessment process are clear and precise and fast, and to provide them to measure the availability requireme
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This research is based on the study of common praise in Mutanabbi and Ibn Hani Al-Andalusi as the main purpose in poetry poets, and balance between them;
The research was divided into two topics, presented by introductory introduction for the purpose of praise, and the concept of budget in Arab criticism, and then presented a brief overview of the lives of poets.
In the first section, I dealt with the common objectivity of the poets, such as the subject of sincerity in praise, hyperbole in the person of Mamdouh, and self-esteem when asked, in addition to the most common characteristics in t
... Show MoreHorizontal wells are of great interest to the petroleum industry today because they provide an attractive means for improving both production rate and recovery efficiency. The great improvements in drilling technology make it possible to drill horizontal wells with complex trajectories and extended for significant depths.
The aim of this paper is to present the design aspects of horizontal well. Well design aspects include selection of bit and casing sizes, detection of setting depths and drilling fluid density, casing, hydraulics, well profile, and construction of drillstring simulator. An Iraqi oil field (Ajeel field) is selected for designing horizontal well to increase the productivity. Short radius horizontal well is suggested fo
The present study aimed to evaluate sera TGF- ?1 concentration in patients with urinary bladder carcinoma (UBC). All malignant of them was transitional cell carcinoma (TCC) type , patients with urinary bladder disorders (UBD ) and healthy control , and to study the correlation between sera TGF-?1 levels and tumor stages and grades in UBC patients . A direct ELISA test was used to quantify the seraTGF-?1 concentrations in sera of 58 patients with urinary bladder carcinoma UBC of different grades (G) and stages (T) all malignant of them was transitional cell carcinoma (TCC) type , 15 from patients with UBD and 15 healthy subjects . Sera levels of TGF-?1 were elevated in patients with UBC and UBD compared to healthy (P ? 0
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This study assessed the advantage of using earthworms in combination with punch waste and nutrients in remediating drill cuttings contaminated with hydrocarbons. Analyses were performed on day 0, 7, 14, 21, and 28 of the experiment. Two hydrocarbon concentrations were used (20000 mg/kg and 40000 mg/kg) for three groups of earthworms number which were five, ten and twenty earthworms. After 28 days, the total petroleum hydrocarbon (TPH) concentration (20000 mg/kg) was reduced to 13200 mg/kg, 9800 mg/kg, and 6300 mg/kg in treatments with five, ten and twenty earthworms respectively. Also, TPH concentration (40000 mg/kg) was reduced to 22000 mg/kg, 10100 mg/kg, and 4200 mg/kg in treatments with the above number of earthworms respectively. The p
... Show MoreDirect measurements of drag force on two interacting particles arranged in the longitudinal direction for particle Reynolds numbers varying from J O to 103 are conducted using a micro-force measurement system. The effect of the interparticle distance and Reynolds number on the drag forces is examined. An empirical equation is obtained to describe the effect of the interparticle distance (l/d) on the dimensionless drag.
Schiff bases (SBs) represent multipurpose ligands that can be prepared from the concentration of prime amines with carbonyl clusters. Creation of SB transition metal compounds via as ligands has opportunity of attaining coordination complexes of abnormal arrangement and stability. These transition metal compounds have extraordinary attention as a consequence of their dynamic portion in metalloenzymes and as biomimetic prototypical complexes as a result of their proximity to usual enzymes and proteins. These complexes are imperative in medicinal disciplines owing to their widespread range of biological actions. They mostly exhibit organic actions involving antifungal, antibacterial, antitumor, antidiabetic, herbicidal, antiproliferative, ant
... Show MoreThis study represents an attempt to develop a model that demonstrates the relationship between HRM Practices, Governmental Support and Organizational performance of small businesses. Furthermore, this study assay to unfold the socalled “Black Box” to clarify the ambiguous relationship between HRM practices and organizational performance by considering the pathway of logical sequence influence. The model of this study consists two parts, the first part devoted to examining the causal relationships among HRM practices, employees’ outcomes, and organizational performance. The second part assesses the direct relationship between the governmental support and organizational performance. It is hypothesized that HRM practices positively influ
... Show MoreThere are many events which causes nonproductive time (NPT) in the drilling industry. The mostly effective in this NPT is pipe sticking event. A considerable amount of time and resources can be spent in efforts to free a stuck pipe. In addition, Unsuccessful fishing operations results in costly alternatives including side-tracking. The drilling in Khabaz oil field poses many operational challenges among of them stuck pipe , lost circulation, flow of salt water during drilling, and hole caving. Stuck pipe can be considered the quite difficult problem in Khabaz oil field due to associated incidents which lead to NPT activities.Well Khabaz -34 was selected to study the problem of stuck pipe in this field. An analysis of stuck pipe even
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Glass Fiber Reinforced Polymer (GFRP) bars have gained popularity as a corrosion-resistant alternative to traditional steel reinforcement in Reinforced Concrete (RC) elements. This study investigates the flexural behavior of PRC panels reinforced with GFRP bars. The study variables included the GFRP reinforcement ratio and the number of embedded steel section distributions. Six concrete panels were fabricated, each measuring 2500 mm in length, with a rectangular cross-section of 750 mm in width and 150 mm in thickness. All panels were reinforced with GFRP bars and divided into two groups based on the reinforcement ratios of 0.532% and 0.266%. For each group, one panel served as the control specimen, while the remaining two were inte
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