Background: The marginal adaptation has a key role in the success and longevity of the fixed dental restoration, which is affected by the impression and the fabrication techniques .The objective of this in vitro study was to evaluate and compare the marginal fitness of lithium disilicate crowns using two different digital impression techniques (direct and indirect techniques) and two different fabrication techniques (CAD/CAM and Press techniques). Materials and Methods: Thirty two sound upper first premolar teeth of comparable size extracted for orthodontic reason were selected in this study .Standardized preparation of all teeth samples were carried out with modified dental surveyor to receive all ceramic crown restoration with 1 mm deep chamfer finishing line, 4 mm axial length and 6 degree convergence angle. Half of the teeth were duplicated and poured in type IV dental stone to have sixteen dies and then these dies and the remaining teeth divided in to two groups according to the type of digital impression techniques (n=16) as follow: Group A: Indirect digital impression technique scanned by inEos X5 camera; Group B: Direct digital impression technique scanned by CEREC AC Omnicam camera. Each group was subdivided according to the technique of fabrication into two subgroups (n=8): Press technique using IPS e-max press (A1, B1); CAD/CAM technique using IPS e-max CAD (A2, B2).Marginal gaps were evaluated on the prepared teeth at four defined points on each aspect using digital microscope at a magnification of (280X). One way ANOVA and LSD tests were used to identify and localize the source of difference among the groups. Results: The results showed that indirect digital impression with IPS e-max CAD/CAM group A2 revealed the poorest marginal integrity with (55.93 μm ± 3.300). Group B2 and group A1 were next in line with(44.49 μm ± 6.840 and 37.74 μm± 5.433) respectively, while in the first group of restorations, the result of 29.9 μm ± 5.534 obtained with direct digital impression with pressable ceramic was clearly better. Conclusions: All the tested digital impression techniques showed clinically acceptable accuracy and intraoral scanning with pressable ceramic significantly enhanced the marginal fit
The current research deals with studying the aesthetics of symbolic values in the design of internal spaces and their connotations through their existence as a material value, as well as the symbolic meanings and their connotations that touch the spiritual and emotional side of the human being as an intangible value, and the research included four chapters, so the research problem was embodied by the following question (What is the role of values Symbolism and aesthetics in the design of interior spaces)? Therefore, the aim was to clarify the role of symbolic values and their aesthetics in the design of internal spaces. The first chapter included the importance of research, the need for it, the limits of the research and its terminology.
... Show MoreThe aims of research is diagnose and indicate the role of fairness in the work of accounting, which is important in reducing the unacceptable practices to manage earnings by economic units, As well as the interpretation and indicate Ethical inside in the accounting and accountants in particular practices in the area of earnings management to reduce the negative effects of the practice and display the results mentioned acts according to what is supposed to be for the purposes of service users, Researchers have identified that one hypothesis, that "Fairness of accountants in of their work accounting lead to a reduction of earnings management practices". The results suggest that the accounting practices that lead to the manipu
... Show MoreGender has considered and become a new trend in women's studies, as it reflects the behaviors, roles and attitudes imposed by society on its members in accordance with their biological nature,with focusing on gender rather than on concentration on women, which is closely linked to the vision that concentrates on women's problems which are not primarily according to their biological differences But rather to a greater extent to social, cultural, historical and religious barriers and Obstacles.
Therefore, the qualitative division due to the concept of "gender" is not a rigid biological division, but is relied on the broad general context through which the social division of work is done. Thus, content in the pages of Facebook with high-
Chromium (Cr), a first-series transition metal with a standard atomic mass of approximately 52 g/mol, plays a sophisticated role as an essential trace element in human and animal physiology. Characterized by its diverse oxidation states most notably the highly stable Cr3+ this micronutrient functions primarily as a biochemical potentiator of insulin action. Through the activation of the low-molecular-weight chromium-binding substance, chromodulin, chromium amplifies insulin receptor tyrosine kinase activity, thereby facilitating efficient glucose uptake and the metabolism of carbohydrates, proteins, and lipids. Beyond glycemic control, chromium serves as a critical modulator of lipid profiles, stimulating lipase activity to reduce very low-
... Show MoreThe main theme of this thesis could be divided into three objectives : The first is to define and classify integral equations with one and multiple delay, including Fredholm, Volterra and integro-differential equations (Retarded, Neutral and Mixed types). While the second and popular objective of this work is to study the inverse problems related to delay integral equations by using non-classical variational formulation method. Some examples are given for each of the discussed type of delay integral equations. Also, a study to the direct and inverse problems related to integral equations with multiple delay, also considered as a third objective. Several examples are given for each type of these equations. Finally, the suggested approach
... Show MoreThe large number of failure in electrical power plant leads to the sudden stopping of work. In some cases, the necessary reserve materials are not available for maintenance which leads to interrupt of power generation in the electrical power plant unit. The present study, deals with the determination of availability aspects of generator in unit 5 of Al-Dourra electric power plant. In order to evaluate this generator's availability performance, a wide range of studies have been conducted to gather accurate information at the level of detail considered suitable to achieve the availability analysis aim. The Weibull Distribution is used to perform the reliability analysis via Minitab 17, and Artificial Neural Networks (ANNs) by approaching o
... Show MoreBackground: The insertion torque (IT) values and implant stability quotient (ISQ) values are the measurements most used to assess primary implant stability. This study aimed to assess the relationship between ISQ values and IT. Materials and methods: This study included 24 patients with a mean (SD) age of 47.9 (13.64) years (range 25-75 years). The patients received 42 dental implants (DI), 33 in the mandible and 9 in the maxilla. The DI were installed using the motorized method with 35 Ncm torque, When DI could not be inserted to the requisite depth by the motorized method, a hand ratchet was used and the IT was recorded as ˃ 35 Ncm. Implant stability was measured utilizing Osstell® ISQ. The secondary stability was measured after 16
... Show MoreA field experiment was carried out during two winter season 2013, 2014 at the field of the Department of Field Crops, College of Agriculture, University of Baghdad, to study the effect of seeds soaking with Gibberellic acid and foliar with Abscisic Acid on the growth, yield, and content of Anise oil seeds using factorial experiment within RCBD design with three replicates. The seeds was treated within GA3 were soaked with two concentrations of 30, and 60 mg. litter-1 in addition to without soaking and the code has been B0 , B1 , B2 overlapped these transactions with two concentrations of Abscisic Acid 3, and 6 mg. litter-1 in addition to without foliar A0 , A1 , A2The seeds to be treated with GA3 are soaked for 24 hours prior
... Show MoreThe current study aims to examine the level of problems faced by university students in distance learning, in addition to identify the differences in these problems in terms of the availability of internet services, gender, college, GPA, interactions, academic cohort, and family economic status. The study sample consisted of (3172) students (57.3% females). The researchers developed a questionnaire with (32) items to measure distance learning problems in four areas: Psychological (9 items), academic (10 items), technological (7 items), and study environment (6 items). The responses are scored on a (5) point Likert Scale ranging from 1 (strongly disagree) to 5 (strongly agree). Means, standard deviations, and Multivariate Analysis of Vari
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