The purpose of this study is to investigate the histopathological response of dentinopulpal
response of human teeth to the Er: YAG laser cavity preparation in comparison with the conventional
class I cavity preparation. Thirty five sound human upper and lower first premolar teeth which were
needed to be extracted for orthodontic purposes were used in the study. Regarding to the method of
cavity preparation, the teeth were grouped into three groups; Group1; Control group which consists of
seven sound teeth without cavity preparation, Group2; Conventional cavity preparation group and group
3; Er: YAG laser cavity preparation group. Each of Group2 and3 consists of fourteen teeth that is
subdivided into: A. 7teeth that extracted after two days after cavity preparation and B. 7 teeth that
extracted after twenty-one days after cavity preparation. Er: YAG Laser device emits radiation at
wavelength of 2940 nm in the infrared region. The laser irradiation was performed in a non-contact mode
with a focused beam of (energy density of 155985.96 mJ /cm2, energy of 600 mJ and a PRRs of 6 Hz for
enamel preparation) and (energy density=64994.151 mJ /cm2, energy = 250 mJ and a PRRs=4 Hz for
dentin preparation) with a spot diameter of 0.7mm at 12-15 mm distance and at right angle to the tooth
surface as possible. The histopathological results of the cavities prepared by Er: YAG Laser revealed the
early proliferation of the odontoblasts in the odontoblastic layer of the coronal part of the pulp which led
to the early formation of the reparative dentin in comparison to those prepared by conventional method.
It can be concluded that the use of the Er: YAG laser in class I cavity preparation has proved to be an
efficient technique in comparison to the conventional cavity preparation.
The building of the Babylonian theater is considered as one of the distinctive buildings where its foundations have remained steadfast in the face of geographical changes, social's erosion and groundwater that threatened almost all traces of Babylon despite the destruction of the outer structure of the building. The general directorate of antiques performed prospection for those foundations (the ground map), and then the building was completed by new bricks over the original scheme. It became clear when examining the building; its components and foundations, that the building is unique in comparison with the old buildings of the world throughout Iraq. There are similar buildings in other places like Jordan and North Africa such as
The Indian costus plasma properties are investigated including electron temperature (Te), "electron density (ne)", "plasma frequency (fp)", " Debye sphere length", and amount of Debye(Nd), using the spectrum of optical emission technique. There are several energies used, with ranging from 300 to 600 mJ. The Boltzmann Plot is used to calculate the temperature; where as Stark's Line Broadening is used to calculate the electron density. The Indian costus was spectroscopically examined in the air with the laser at 10 cm away from the target and the optical fiber at 0.5 cm away. The results were obtained for an electron temperature range of (1.8-2.2) electron volts (ev) and a wavelength range of (300-600) nm. The XRF analysis reveals th
... Show More
Dental caries (tooth decay) is one of the most prevalent infectious disease and although of multifactorial origin, Streptococcus mutans is considered the principal pathogen in its development (i.e. bacterial processes damage hard tooth structure (enamel, dentine and cementum), producing dental cavities (holes in the teeth). The bactericidal properties of the Nd:YAG laser has been researched analyzing its use in caries prevention and bacterial reduction. One hundred twenty five samples were collected from carious teeth and isolated bacteria were diagnosed using microscopic examination, culture, biochemical tests, and Api 20 strep system. The results of this study showed that a noticeable decrease in the viability of Streptococcus mutans w
... Show MoreThe research aims to reach a set of objectives concerning creation a clear vision about conceptual, philosophical and practical dimension of relations, and effects between knowledge management, costumer orientation and competitiveness to construct a framework of a pragmatic model as a solution to research problem and its questions which the main one is about the role of knowledge management and costumer orientation in competitiveness of business organizations. To achieving this goal, it was necessary to make, in priory, a review and discussion to the theoretical dimension of research variables to have a clear vision about constructing hypostatical research model implying a set of hypotheses which, by proving them in companies studied, repr
... Show More
(1)
(1)
NeighShrink is an efficient image denoising algorithm based on the discrete wavelet
transform (DWT). Its disadvantage is to use a suboptimal universal threshold and identical
neighbouring window size in all wavelet subbands. Dengwen and Wengang proposed an
improved method, which can determine an optimal threshold and neighbouring window size
for every subband by the Stein’s unbiased risk estimate (SURE). Its denoising performance is
considerably superior to NeighShrink and also outperforms SURE-LET, which is an up-todate
denoising algorithm based on the SURE. In this paper different wavelet transform
families are used with this improved method, the results show that Haar wavelet has the
lowest performance among
The present study was conducted as atrial to treat secondary hydatidosis in white mice of species Mus musculus. (Balb/c strain), experimentally infected with secondary hydatid cysts of sheep origin. The immunization process was carried by using CF/PS antigen which consist hydatid cyst fluid (CF) antigen, and protoscolices (PS) antigen mixed together and by using two concentrations 7.5, 15 mg/ml. Then derivatives of Benzimidazole, Mebendazole (M) and drugs Albendazole (A) were used 10 and 40 μm/gm body weight respectively. The mixture of drugs was used one week after challenged dose. Criteria taken into consideration to define the activity of the immunization and chemotherapy in this study were reduction in the numeral of cysts, the coeffic
... Show More
(2)
The research problem was to identify the impact of monetary policies on economic growth in the oil and non-oil countries. The researcher chose the Republic of Iraq as an example for the oil countries and the Arab Republic of Egypt as an example for the non-oil countries to hold a comparison on the impact of monetary policies.
The research found that the monetary policies and their tools in the Iraqi economy affect the rate of GDP growth by 73%, which shows the strong impact of monetary policies on the economic growth in the Iraqi economy as an example of an oil state. GDP growth rate of 61%, indicating the impact of monetary policies on economic growth in the
The study addresses the problem of stagnation and declining economic growth rates in Arab countries since the eighties till today after the progress made by these countries in the sixties of the last century. The study reviews the e
... Show More
Many societies have some sports that play a pivotal role in enhancing human physical strength and martial arts and preserving religious values and beliefs. The most prominent of these traditional heroic sports are Zurkhaneh and Sumo, two sports that have their historical origins in the Iranian and Japanese cultural heritage. The research aims at shed light on the historical origins, symbolic rituals, and traditional elements of the sports of Zurkhaneh and Sumo, and to highlight the distinctive characteristics of the sports of Zurkhaneh and Sumo through objective analysis and comparison. The methodology used in this research is the historical approach, using the method of comparative analysis. This method includes analyzing information deriv
... Show More