Background: Crown preparation of vital teeth involve the removal of a sound tooth structure, and when enamel removed this lead to exposed dentin with an increase in the number of open dentinal tubules also the diameter of dentinal tubules will increase, furthermore lead to increase movement of fluids inside the tubules all that causes post preparation sensitivity. The aim of this study is to evaluate the effect of desensitizing by Er:Cr:YSGG laser on shear bond strength of prepared tooth and resin cement. Materials and methods: Thirty sound maxillary premolars, grouped into three groups(n=10). Group A is the control group, group B irradiated by Er:Cr:YSGG laser with (0.25 W, 20 Hz, 10%water and air), group C irradiated by Er:Cr:YSGG laser with (0.5 W, 20 Hz, 10% water and air). Results: SEM examination showed complete occlusion of opened dentinal tubules after laser irradiation of both groups that irradiated with laser. Statistical analysis showed significant increase in surface roughness in group B and C. SBS was significantly increase in group B with no significant increase in group C. Conclusion: Er:Cr:YSGG laser can occlude open dentinal tubules without and adverse effect on the retention of the restoration, on the contrary it increase bonding strength. And this increasing was significant in group B with (0.25W, 20 Hz, 10 % water and air). suggestion: so the parameters used in group B (0.25 W, 20Hz, 10 % water and air) is recommended for desensitizing prepared tooth and induce enhancement to the bonding strength of resin to tooth surface.
Firstly, in this study, a brief updated description and applications of different solar collectors used in renewable energy systems for supplying electric and thermal energy was presented. Secondly, an attempt was made to utilize tilting orientation of solar collector for maximizing collector energy with time in respect to horizontal orientation. For energy calculation, global solar radiation was used since they are directly related. For that purpose, field measurements of half-hourly radiation on two flat panels of tilting and horizontal orientations were carried out throughout 8-month period under local climate of Baghdad. Then, energy gain and radiation level averages were calculated based on the field radiation
... Show MoreElectricity consumption for household purposes in urban areas widely affects the general urban consumption compared to other commercial and industrial uses, as household electricity consumption is affected by many factors related to the physical aspects of the residential area such as temperature, housing unit area, and coverage ratio, as well as social and economic factors such as family size and income, to reach the extent of the influence of each of the above factors on the amount of electricity consumed for residential uses, a selected sample of a residential area in the city of Baghdad was studied and a field survey conducted of the characteristics of that sample and the results analyzed and modeled statistically in relation to the amo
... Show MoreThe aim of this research sought to assess the background radiati on levels of medicinal plant samples in Iraq.The D, AED, and ELCRThe D values are 0.164 ± 0.006 µSv/h.The radiation dose outputs from the afore mentioned research were juxtaposed with the safety threshold of 0.247 µSv/h set by the United Nations Scientific Committee on the Effects of Atomic Radiation (UNSCEAR) in 2008 and the National Council on Radiation Pr otection and Measurements (NCRP) in 2009.The radiation exposure for all samples in this investigation is within the permissible limits.Additionally, t he AED values obtained from microsieverts per hour are (1.31 ±0.0326 mS v/y), indicating variability, with a maximum permissible limit of 2.4 mSv/y ear, as per t
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The Quranic discourse focused on a lot of vocabularies that carry goals that help man to acquire good, according to a methodology relies on adopting lofty ideas and values. The individual towards society, and the responsibility of society towards the individual. In our present age, the Muslim individual lives in a state of confrontation with deviant ideas, which unfortunately possess the means that make their impact great on society. The study concluded that the Holy Quran contains indicators and determinants of misguided and deviant thought, Which must be avoided because of the seriousness of its effects. Religion, in its general sense, represents a culture that transcends the limits of human ins
... Show MoreThis paper deals with constructing mixed probability distribution from exponential with scale parameter (β) and also Gamma distribution with (2,β), and the mixed proportions are ( .first of all, the probability density function (p.d.f) and also cumulative distribution function (c.d.f) and also the reliability function are obtained. The parameters of mixed distribution, ( ,β) are estimated by three different methods, which are maximum likelihood, and Moments method,as well proposed method (Differential Least Square Method)(DLSM).The comparison is done using simulation procedure, and all the results are explained in tables.
Accountancy unit is looked is upon as unit that established for the purpose achieve it goals and programmers for unlimited time. Unless otherwise take place such as liquation whether voluntary or mandatory. Thus going concern logic is considered to be the logical foundation witch the familiar accounting principles are based upon. The future of a Company real its financial statues and position and the extent of it ability to face events in future. Hence the success and continuity its activities depend on the extent of the company activity to generate profits. And its ability to retain appropriate liquidity to serve its debts.
Therefore financial statements of the company consider to be on
... Show MoreThe research aims to contribute to the consolidation of scientific knowledge of compliance control and its role in verifying the proper disposal of funds to manage the wheel of the economy towards achieving targeted development and preserving public money, as well as clarifying the role of tax revenues in strengthening the public treasury and achieving social justice. The analytical descriptive approach was adopted in the process of analyzing The quantitative data collected through personal interviews, and the research reached a set of conclusions, the most important of which is the contribution of compliance control according to its three principles. (Transparency, accountability, and inclusiveness) on the availability
... Show MorePorosity and pore structure are important characteristics of pharmaceutical tablets, since they influence the physical properties, such as mechanical strength, density and disintegration time. This paper is an attempt to investigate the pore structure of four different paracetamol tablets based on mercury porosimetry. The intrusion volumes of mercury were used to calculate the pore diameter, pore volume and pore size distribution. The result obtained indicate that the variation of the pore volume in the tablets followed the sequence:- S.D.I. Iraq? Pharmacare,Dubai-U.A.E.? Bron and Burk(UK) London?Lark Laboratories(India), while the variation of surface area followed the sequence:- S.D.I. Iraq? Lark Laboratories(India)? Pharmacare,Dubai-U.A
... Show MoreThe present study aimed to examine the effect of endosulfan insecticide on some molecular and biochemical parameters in white mice. Thirty mice were separated randomly into three groups for treatment with endosulfan. One group (G1) served as the control, while the other two groups received intraperitoneal injections of endosulfan G2 (3 mg/kg) and G3 (17 mg/kg) twice a week for 21 and 45 days, respectively. A biochemical study by measuring liver function parameters, including (alanine aminotransferase (ALT) and aspartate aminotransferase (AST)) and kidney function parameters, including (Blood Urea and Creatinine) and malondialdehyde (MDA), catalase activity (CAT). This study also tested DNA damage by comet assay (normal%, low%, med
... Show MoreThis is a brief research in which I tried to briefly explain the care that the Holy Qur’an received during the era of the Prophet, may God bless him and grant him peace, from the Prophet, may God bless him and grant him peace, and all of his honorable companions, may God bless him and grant him peace. I made this research in an introduction and two chapters, the first chapter I made it entitled: About the Holy Qur’an, in which I talked about general investigations about the Holy Qur’an, such as the definition of the Holy Qur’an and the difference between it and the hadith Qudsi and the hadith of the Prophet, then I mentioned a part of the virtues of the Holy Qur’an in general and the virtues of some surahs in particular, and th
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