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.
With the increasing rate of unauthorized access and attacks, security of confidential data is of utmost importance. While Cryptography only encrypts the data, but as the communication takes place in presence of third parties, so the encrypted text can be decrypted and can easily be destroyed. Steganography, on the other hand, hides the confidential data in some cover source such that the existence of the data is also hidden which do not arouse suspicion regarding the communication taking place between two parties. This paper presents to provide the transfer of secret data embedded into master file (cover-image) to obtain new image (stego-image), which is practically indistinguishable from the original image, so that other than the indeed us
... Show MoreThe research involves preparing gold nanoparticles (AuNPs) and studying the factors that influence the shape, sizes and distribution ratio of the prepared particles according to Turkevich method. These factors include (reaction temperature, initial heating, concentration of gold ions, concentration and quantity of added citrate, reaction time and order of reactant addition). Gold nanoparticles prepared were characterized by the following measurements: UV-Visible spectroscopy, X-ray diffraction and scanning electron microscopy. The average size of gold nanoparticles was formed in the range (20 -35) nm. The amount of added citrate was changed and studied. In addition, the concentration of added gold ions was changed and the calibration cur
... Show MoreSilymarin (SM) is a plant extract obtained from Silybum marianum( milk thistle) . It is class II type drug according to Biopharmaceutics Classification System with low bioavailability due to its low solubility.
Micro/nanonization during crystallization, surface modification and crystal structure modification may improve the dissolution rate of poorly water-soluble drugs.
The aim of this study was to increase the water solubility and dissolution rate of SM by in-situ micronization using solvent change either by stirring or ultrasonic method. Stabilizers like Gelatin, PVP-K30, HPMC15, Pulullan were used to stabilize the prepared ultrafine crystals. Effect of type and concentration of hydrophilic polymer, solv
... Show MoreIn this study, an improved process was proposed for the synthesis of structure-controlled Cu2O nanoparticles, using a simplified wet chemical method at room temperature. A chemical solution route was established to synthesize Cu2O crystals with various sizes and morphologies. The structure, morphology, and optical properties of Cu2O nanoparticles were analyzed by X-ray diffraction, SEM (scanning electron microscope), and UV-Vis spectroscopy. By adjusting the aqueous mixture solutions of NaOH and NH2OH•HCl, the synthesis of Cu2O crystals with different morphology and size could be realized. Strangely, it was found that the change in the ratio of de-ionized water and NaOH aqueous solution led to the synthesis of Cu2O crystals of differen
... Show MoreBackground: Decalcification of surface enamel adjacent to fixed orthodontic appliances, in the form of white spot lesions, is a wide spread and familiar well-known side effect of orthodontic treatment. The present study was carried out to evaluate the effect of enamel protective agent (Clinpro white varnish) on shear and tensile bond strength of Dentaurum orthodontic stainless steel brackets by using 3M Unitek and Ormco as orthodontic adhesive agents. Materials and methods: Sixty-four extracted human upper first premolar teeth were selected and randomly divided into two groups with 32 teeth each, representing the shear and tensile bond strength testing groups. Then according to the type of bonding adhesive and the addition of Clinpro before
... Show MoreThe researcher seeks to get scientific facts through knowing the relationship between the priorities of Yemeni audience in follow-up paper daily newspapers compared to surfing publics the online journalism sites and the nature of information obtained from online journalism sites and printed paper newspapers and the impact of the daily newspapers in the priority of issues and political events among a sample of a group of Yemeni readers in order to identify the extent to keep up the paper daily newspapers of the development in the field of online journalism and the extent of reading paper newspapers under the intense competition by online journalism sites, and are paper newspapers able to keep pace with the actual developments provided by
... Show MoreThe formula of Ijarah and Ijarah ending with ownership is one of the investment formulas in Islamic banks, so this research has shed light on it in order to benefit from the experiences of the research sample banks, This research aims to find a reliable way for Iraqi Islamic banks, namely (leasing and leasing ending with ownership) in order to invest their money without usurious interests, The problem of the research emerges through the lack of awareness of the Iraqi Islamic banks to work with different Islamic financing formulas and their inability to invest their money through the adoption of their administrations for different formulas, including the leasing, and this is reflected in the decrease and fluctuation of its profits, Theref
... Show Moreان من اهم القضايا التي تثيرها المعرفة البشرية في تجلياتها، وتعبيراتها المفاهيمية، تكمن في مدى تأصلها وانتمائها الى البنى والتشكيلات الموضوعية (في مستوياتها التاريخية) التي تسعى لتفسيرها وادراكها ومضاهاتها. فالينبوع الذي يغرف منه الفكر مادته هو الكيان الاجتماعي المتموضع خارج الوعي والايدولوجيا.
ان قدرة الوعي على ادراك الواقع الموضوعي بخصائصه العامة يشكل الشرط الضروري لاكتساب الوعي ل
... Show MoreNeuroendocrine differentiation has been mentioned in many cancers of non-neuroendocrinal organs, involving the gastrointestinal tract. In contrast, the correlation of focally diffused neuroendocrine differentiation in colorectal adenocarcinoma with neuroendocrine cell hyperplasia has not been somewhat reported. The objective of this research is to study the relationship between neuroendocrine cell hyperplasia and neuroendocrine differentiation in colorectal adenocarcinoma and to find the correlation of neuroendocrine differentiation and VEGF expression with clinicopathological parameters of colorectal adenocarcinoma. Methods employed in the current study were including eighty-one patients with colorectal cancer. Formalin fixed paraffin e
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