The purpose of this work was to study the effects of the Nd:YAG laser on exposed dentinal
tubules of human extracted teeth using a scanning electron microscope (SEM). Eighty 2.5mm-thick
slices were cut at the cementoenamel junction from 20 extracted human teeth with an electric saw. A
diamond bur was used to remove the cementum layer to expose the dentinal tubules. Each slice was
sectioned into four equal quadrants and the specimens were randomly divided into four groups (A to D ).
Groups B to D were lased for 2 mins using an Nd:YAG laser at 6 pulses per second at energy outputs of
80 , 100 and 120 mJ. Group A served as control. Under SEM observation, nonlased specimens showed
numerous exposed dentinal tubules. SEM observation revealed that application of Nd:YAG laser at
energy output of 80 mJ may cause melting of dentin and partial closure of exposed dentinal tubules
without dentin surface cracking. But when the energy output raised to 100 and 120 mJ more sealing of
dentinal tubules occurs. Heat generation occurred in all lased groups but the amount of temperature
increase was within the permissible limits(less than 5.5⁰C). The measured sealing depths were from 3-
5μm for groups B-D and the width of the created groove was 30μm in all lased groups. In conclusion
lasing with nanosecond Nd:YAG with a wavelength of 1064nm at 120mJ with 6Hz for 2 minutes (group
D) shows the efficient laser parameters for complete sealing of exposed dentinal tubules without
temperature increase to the damaging level of the pulp tissue.
The current investigation conducted to examine the anatomical aspects of the Arum colocasia L. cultured in Iraq. The study included the anatomical characteristics of the different plant parts, including the root, stem and leaf, the results of the study on the vegetative parts were shown the important anatomical characteristics in terms of the form of the sections reviewed and vertical in them, and the study of their tissues, as well as the stomata complexities and the thickness of the epidermis, vascular bundles, pith, additionally the dimensions of mesophyll and in blade of the leaf. The research was conducted as it is one of the monocotyledon plants and because of the lack of anatomical studies on it, therefore it was studied to know the
... Show MoreThe study aims at showing the effect of basil oil on the sensory properties of the laboratory biscuits. the results show the sensory valuation before and after the storage. the (A4) equation exceeds 15% of T exchange (3 , 4 , 5 g. basil 19 , 55 g . fats )in most of the studied sensuous qualities. Then, the (A5) equation of 20% exchange percentage (4.60g. basil oil + 18.40g. fats). Then, the (A3) equation of 10% exchange percentage (2.30g. basil oil + 20.70g. fats). Then the (A2) equation of 5% exchange percentage (1.5g. basil oil + 21.85g. fats). Finally, the control equation (A1) received the lower value of sensuous evaluation and general acceptance. Abstract differences also appeared at denotation level 0.05 between the (A2)
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Stylistics represents a modern approach in understanding the literary text through the linguistic patterns that form it. The distinctive phenomena that the text includes constitute special features in it. As well as exploring its aesthetic aspects through description and analysis at the same time. The close link between stylistics and linguistics made stylistics occupy a prominent place in modern literary criticism.
In this regard, we do not want to dwell on the different directions of stylistics. Rather, we will prolong the discussion in the study of the style as a (deviation. Aversion) from the original. Because this trend plays on the chord of the paradox between the surface structure and the deep structure, especially when the sur
The issue of the development of Qur'anic studies for the tasks, and the first thought of minds and multiple understandings, and the most precious ideas, and the alternatives were floated, and varied visions, especially as we live in an era exploding knowledge, and complicate secretions, and scramble his ideas, and to devise intellectual approaches To achieve the witnesses of civilization in the words of the Almighty (to be martyrs on the people) Surat Al - Baqarah / 143 attendance and participation in the achievement and a positive interaction with the participants of humanity and civilization in the light of the meaning (to know) rooms / 13.
Therefore, we must emerge from the one-dimensional view of the Koran to the complex mindset t
The history of the Olympic movement in Iraq is a rich history that reflects the interest of Iraqi governments and society in sports, the social and economic conditions, and international relations, and highlights the intersection of sports and politics and the impact of global events on local sports development. Therefore, providing a valuable insight into the reality of the participation and results achieved by Iraq in the Olympic Games for the period under study helps in giving a broader understanding of Iraq’s position in the global sports community. The research aims to document the important events in the development of the Olympic movement in Iraq for the period (1929-2000) and explore the formation and development of the Iraqi Olym
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Earth dams are constructed mainly from soil. A homogenous earth dam is composed of only one material. The seepage through such dams is quite high. Upstream impervious blanket is one of the methods used to control seepage through the dam foundations. Bennet's method is one of the commonly used methods to design an impervious upstream blanket. Design charts are developed relating the length of blanket, total reservoir head, total base width of the dam (excluding downstream drainage), the coefficient of permeability of the blanket material, blanket thickness, foundation thickness, and coefficient of permeability of the foundation soil, based on the equations governing the Bennet's method for a homogenous earth dam with a blanket of uniform
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Background: Elastomeric chains are one of the most commonly used force delivery systems. They have the ability to exert a continuous force, convenience of use, compatibility to oral environment and cost effectiveness but one of the inherited disadvantages is force degradation. Materials and methods: This in vitro study was designed to evaluate the effect of alcohol presence in mouthwashes on force decay of different configurations of clear elastomeric chains from (Ortho Technology company) which are: closed , short and long under the effect of time at (Initial, 1, 2, 3 and 4 weeks) intervals with exposure to different chemical solutions. A total (540) modules of elastomeric chains of three different types (long, short and closed) trans
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