Abstract: Objectives: To investigate the effect of temperature elevation on the bonding strength of resin cement to the zirconia ceramic using fractional CO2 laser. Background: Fractional CO2 laser is an effective surface treatment of zirconia ceramic, as it increases the bonding strength of zirconia to resin cement. Methods: Thirty sintered zirconia discs (10 mm diameter, 2 mm thickness) were prepared and divided to three groups (N=10) and five diffident pulse durations were used in each group (0.1, 0.5, 1, 5 and 10 ms). Group A was treated with 10 W power setting, group B with 20 W and group C with 30 W. During laser irradiation, temperature elevation measurement was recorded for each specimen. Luting cement was bonded to the treated zirconia surfaces and cured for 30 seconds. Shear bond strength was evaluated by a testing machine (universal) with bond failure mode determination. Results: The lowest temperature elevation measurement of the irradiated specimen which gave maximum shear bond strength was about 1.6±0.3 Ċ higher than ambient room temperature (27±0.2 ºC). Apparent micromechanical irregularities were seen in the treated samples and cracks formation with increased pulse duration and power setting were also observed. Conclusions: The temperature elevation is a vital factor in the surface roughness of zirconia ceramic with fractional CO2 laser irradiation and the lowest temperature elevation at best shear bond strength of zirconia ceramic to the resin cement is satisfied with the shorter pulse duration of 0.1 millisecond.
The artistic mediation in theater connects the human elements with the material elements in the theatrical production process. The human artistic mediator plays a crucial role in achieving the artistic and expressive goals of the theatrical work, requiring high skills and expertise. Their role involves coordinating and executing the technical aspects of production, such as lighting, sound, set design, costumes, and acting, using their skills and techniques to transform the theatrical text into a successful stage performance. The artistic mediator significantly impacts the quality of the theatrical work and creates a distinct viewing experience for the audience. Technological advancements and continuous updates in theater contribute to th
... Show MoreThe article is devoted to football lexicon in Arabic and Russian. The charr acteristics that determine the coincidence of lexical units in the Arabic and Russian languages are revealed. Football related words and phrases exist in different languages and in most cases they are the same. With the develop ment of football in the world and thanks to the media, new words and terms have become firmly established in the language. In Arabic, Italian and Span ish words are often used, but there are original Arabic phrases, most often consisting of two words - sports journalists and commentators actively use them. The word »mercato« was borrowed from the Italian language; in addi tion, in the Arabic language there is a phrase »Bab al-inti
... Show MoreResearch included the preparation of medicinal substances ( propyl thiouracil). Which is the rule thiourea and related compounds a fundamental rule in preparation fall within the range of drugs of anti-thyroid activity (Antithyroid Drug ) , this drug prevents the thyroid hormone production against excessive activity of the thyroid gland .That the formation of iodine is important for their impact on hormone secretion thyroid , the two types, thyroxin or T4 is the main hormone ,Triiodothyronine or T3, and these hormones released by hormone regulator called (TSH) . Article attend thiourea treatment with an alcohol- soluble sodium and added to the interaction rule b- oxo ester after adjusting the PH=4 output ( propylthiouracil ) the
... Show MoreCollapsible soil has a metastable structure that experiences a large reduction in volume or collapse when wetting. The characteristics of collapsible soil contribute to different problems for infrastructures constructed on its such as cracks and excessive settlement found in buildings, railways channels, bridges, and roads. This paper aims to provide an art review on collapse soil behavior all over the world, type of collapse soil, identification of collapse potential, and factors that affect collapsibility soil. As urban grow in several parts of the world, the collapsible soil will have more get to the water. As a result, there will be an increase in the number of wetting collapse problems, so it's very important to com
... Show MoreThe Arab Islamic art was best known as pure abstraction or realism distorted from what is natural. The two styles, or one of them, was the most prominent in the Islamic arts, such as decoration, photography and architecture. The analogy that was prevalent in the non-Islamic world did not have a presence equivalent the aforementioned styles despite the great openness to the cultures of different countries, which characterized that stage, which resulted from the Islamic conquests, the conversion of many people to the Islamic faith, and their migration to the Islamic cities at the time, bringing with them their arts and methods of formulation. This makes us question the influential references that invite the Arab Muslim artist to follow the
... Show MoreBiodiversity, biological diversity, biological diversity, biological diversity, biological diversity, biological diversity, biological diversity (by developmental factors) environmental factors and environmental factors environmental factors and environmental factors and environmental factors Correlation between biology and the succession of geological and historical factors of living organisms and geological and historical factors to the site and what It is surrounded by natural and tourist attractions and the pursuit of scientific methods in order to advance the studies of biological diversity in the region .
Since the property in Islam is based on the principle of succession , "which made you Khalaúv land and raise yourselves above some degree of Iblukm with Atakm The Lord of the fast punishment and it is Forgiving, Merciful " [cattle : 165 ] and human only Mstkhalaf where " God promised you who believe and do good deeds for Istkhalvenhm Normans in the ground as those before them " [Nur : 55 ] , considering that King God alone any talk about having ownership in Islam in the contemporary sense of ownership , containing three rights are:
1- right to dispose of the right of usufruct tenure
2-The concept is ambiguous as long as that man Mstkhalaf does not have the right to dispose
... Show MoreThe research deals with the structures of the contemporary travelers' buildings in particular, and which is a functional complex installations where flexibility, technical and stereotypes play an important role as well as the human values These facilities must represent physiological and psychological comfort for travelers. TThose are facilities where architectural form plays a distinguished role in reversing the specialty and identity of the building. Hence the importance of the subject has been in forced, as a result for the need to study these facilities and to determine the impact and affects by the surrounding environment, to the extent of the urban, environmental, urban, social, and psychological levels. The importance of the resea
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