Background: This study was formulated to compare the effect of 5%hydrofluoric acid in comparison to 37%phosphoric acid with and without the application of silane on bond strength of composite to porcelain. Materials and Methods: Specimen preparation was divided in to two phases, metal-disks fabrication (8mm-diameter and 4mm-thickness) and ceramic veneering. Thirty two specimens were prepared, sandblasted with 50 μm aluminum oxide, and divided into four groups of eight samples. Groups I and III were etched with 37%phosphoric acid while groups II and IV were etched with 5%hydrofluoric acid; and groups I and II were silaneted while groups III and IV were not. Heliobond, and resin composite were applied to each specimen using a plastic transparent split mold (4mm- diameter and 4mm-height). Specimens were stored in distilled water for 24 hours then thermocycled for 100 cycles. Shear bond strength was determined by a Zwick universal machine at a cross-head speed 5 mm/minute. Results: Mean shear bond strength values were 21.02(group I), 23.31(group II), 4.00(group III), and 18.60(group IV). Paired-t revealed that specimens treated with 5%hydrofluoric acid were significantly higher than those treated with 37%phosphoric acid regardless the use of silane. The use of silane dramatically enhanced the bond strength of composite resin to porcelain for both acids. All specimens treated with 37%phosphoric acid without silane showed adhesive failure, while those treated with 5%hydrofluoric acid showed mostly cohesive failure within ceramic. Conclusion: Silane improved the shear bond strength of composite to ceramic, and hydrofluoric acid performed greater bond strength compared to phosphoric acid.
Quality control is an effective statistical tool in the field of controlling the productivity to monitor and confirm the manufactured products to the standard qualities and the certified criteria for some products and services and its main purpose is to cope with the production and industrial development in the business and competitive market. Quality control charts are used to monitor the qualitative properties of the production procedures in addition to detecting the abnormal deviations in the production procedure. The multivariate Kernel Density Estimator control charts method was used which is one of the nonparametric methods that doesn’t require any assumptions regarding the distribution o
... Show MoreThe Rafidian artist discussed the headdresses of his idols with a varied scholarly momentum, so each idol had its own cover as this door of diversity contributed to the enrichment of Rafidian thought and full knowledge of their ideas and beliefs consistent with their multiple symbolic connections such as architecture, for example. The previous one, if not its entirety.
A research such as this (the discursive connections to the head-covers of the deities of the Mesopotamian civilization) aims to clarify the confusion that occurs through four chapters: The first chapter included: the research problem, the importance of research and the need for it, the objectives of the research, the temporal, spatial and objective limits of research, a
The aim of the current research is to study a topic from the Qur’anic topics, few have researched it and realized its content, so people knew it in one name in the Qur’an in another name, and due to the ancientity of the topic and its contemporaneity, I wanted to write about it. The research has an introduction, three demands, and a conclusion with the most important results of the research:
As for the introduction: It was to indicate the importance of the topic and an optional reason for it.
As for the first requirement: it included the definition of reasoning, its divisions, and its characteristics.
As for the second requirement, it was to indicate the meaning, types, and methods of labeling it.
As for the third require
The issue of the development of Qur'anic studies for the tasks, and the first thought of minds and multiple understandings, and the most precious ideas, and the alternatives were floated, and varied visions, especially as we live in an era exploding knowledge, and complicate secretions, and scramble his ideas, and to devise intellectual approaches To achieve the witnesses of civilization in the words of the Almighty (to be martyrs on the people) Surat Al - Baqarah / 143 attendance and participation in the achievement and a positive interaction with the participants of humanity and civilization in the light of the meaning (to know) rooms / 13.
Therefore, we must emerge from the one-dimensional view of the Koran to the complex mindset t
Walkability as one of the Planning Treatments to Face Epidemics in Cities
Capital Adequacy is on of the most importance of financial position element because its role is enhance against varions risks of Banking procese . Which this risks is a result of the nature of its operations , investment , Financing tools in addition , in order to Faced any clients withdraws un expected .
So This study aim to measure The Capital Adequacy according to basel II and explin the different risk in the Islamic Bank as aresult to nature and different investment and financing tools as participation speculation , murabah and natures of its assets and liabilities related to commercial banks .
Find out we concludes that the Islamic Banks needs to increase the ca
... Show MoreThe research topic dealt with the strategic recovery of the insurance service, which is one of the approaches that have an important role in providing solutions and remedies for the recession that affects companies and hinders them from achieving their strategic goals. The research also addressed the strategic objectives of the company as the rationale and actual guide for companies of all activities in order to protect their systems from deviation for its desired purpose. So the aim of the research is to demonstrate the repercussions of the strategic recovery of the insurance Service represented by (compensation, speed of response, apology, initiative (identifying the problem). The company's strategic goals are represented (prof
... Show MoreThe contemporary art culture is considered a resultant of preceding human civilizations from the early days. At the same time, it got closer to the local privacy, because the contemporary Iraqi potter worked hard to create new art, refusing to base his art on the early works, creating art pieces that contains properties to inherited art and their form significance, in order to create a new identity of his own, bringing an empowerment to his deepened civilization, with the goal to create national identity ideas from one hand, and entity and locality from another. Europeans also followed the direction of our civilization, such as (Picasso, Henry Moore, Barbra Hurth, Brankouzi, Hans Arp,..etc). From this point of view comes the importance o
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