The objective of this study is to determine the efficacy of class V Er:YAG laser (2940 nm) cavity preparation and conventional bur cavity preparation regarding Intrapulpal temperature rise during cavity preparation in extracted human premolar teeth. Twenty non carious premolar teeth extracted for orthodontic purposes were used and class V cavity preparation was applied both buccal and lingual sides for each tooth .Samples were equally grouped into two major groups according to cavity depth (1mm and 2mm). Each major group was further subdivided into two subgroupsof ten teeth for each (twenty cavities for each subgroup). TwinlightEr:YAG laser (2940 nm) with 500mJ pulse energy, P.R.R of 10 Hz and 63.69 J/cm2 energy density was used. The analysis of the data collected revealed that there was highly significant difference between subgroups of each group, i.e., (Er:YAG laser and conventional bur cavity preparation). Also there was a highly significant difference between both group1 and group 2 subgroups (with 1mm and 2mm cavity depth). Best results were obtained from subgroup A which represents class V cavities prepared using Er:YAG laser with energy density of 63.69 J/cm2 .Er:YAG laser cavity preparation with energy density of 63.69 J/cm2 was less temperature rise than conventional bur cavity preparation taking into account the invitro temperature rise of class V cavity preparation.
The current study is concerned with presenting a descriptive study of the history of the city of Astrabath in the sixth century AH. The problem that the research tried to answer is represented in the investigation of historical news, and the study of the most prominent cultural aspects which characterizing that city. The research also aims to reach the geographical location of that city, its name and its suburbs. The importance of the research lies in the knowledge of everything related to the role of the civilization of Astrabath, as well as tracing the entry of the Arabs to it, so that it became a cultural, economic and scientific center and its historical role in the sixth century AH. The research reminde us with the scientific role o
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Approaching the turning of the millennium, the American theatre witnessed an arousing
interest much shown in patients suffering of severe diseases as a subject matter to drama. In a
discussion of Margaret Edson's Wit, the light is shed on how far such patients, who were literally
involved in secular visions during their life-time, become apt to create a different one on their
death beds. The vision newly blossomed becomes much rooted in the spiritual life; it is a
redemptive vision that can amend what those patients' hearts and minds have long ignored.
Further, the human touch that has been ignored during man's healthy secular life is ultimately
needed for the time being. It helps to enhance man's vision towards the
The Logic of Freezers and Animals in the Holy Quran
(2)
The aim of this research is to show the importance of the effective use
of the internet in academic libraries; to improve the services and to increase
the competence of librarians.
The research has given some recommendations to improve the quality
of services and the need for cooperative network among academic libraries.
In this study, the effect of pumping power on the conversion efficiency of nonlinear crystal (KTP) was investigated using laser pump-power technique. The results showed that the higher the pumping power values, the greater the conversion efficiency (η) and, as the crystal thickness increases within limitations, the energy conversion efficiency increases at delay time of (0.333 ns) and at room temperature. Efficiency of 80% at length of KTP crystal (L = 1.75 X 10-3 m) and Pin = 28MW, and also, compare the experimental results with numerical results by using MATLAB program.
The Umayyad era is characterized by the diversity of the subjects and their multiplicity in the literary phenomena. These phenomena are singing phenomena, although they were known in previous eras, they took a distinctive form in the era.
In this light, the researcher tried to prove that singing theory in the Umayyad period was characterized by development and renewal. The research was entitled (evolution and renewal in the theory of singing in the Umayyad era).
The aim of this study is modeling the transport of industrial wastewater in sandy soil by using finite element method. A washing technique was used to remove the industrial wastewater from the soil. The washing technique applied with an efficient hydraulic gradient to help in transport of contaminant mass by advection. Also, the mass transport equation used in modeling the transport of industrial wastewater from soil includes the sorption and chemical reactions. The sandy soil samples obtained from Al-Najaf Governorate/Iraq. The wastewater contaminant was obtained from Al- Musyiebelectricity power plant. The soil samples were synthetically contaminated with four percentages of 10, 20, 30 and 40% of the contaminant and these percentages calc
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