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.
This research is a study in which the researcher follows the al-Najjariya sect, which is attributed to Abi Abdullah al-Hussain bin Muhammad bin Abdullah al-Najjar, who died around (220 AH) and aims to:
1- Finding out the time of the emergence of this sect, and removing the confusion as to whether it was from the origins of the sects, or just an independent sect, or affiliated with one of the famous sects.
2- Standing on the most prominent theological opinions adopted by this sect, and in which of them did the Mu'tazila sect agree, and in which of them did the Sunnis and the community agree.
3- Statement of the most prominent sects that branched out from this sect.
The aim of this study is to determine the organic and inorganic components of bile and gallstones in Iraqi patients. Forty seven patients were included in this study with mean age (53+7) years and BMI (30.82+4.18) Kg/m2. Bile was classified according to its corresponding stones into: Bile of Mixed stones and Bile of pigment stones. IR spectra were studied for both types of stones and their bile in addition to biochemical analysis for organic and inorganic components. The organic components include: (cholesterol, bilirubin, bile salts, and phospholipids), while inorganic components include salts of: (calcium, phosphorus, iron, cupper and magnesium). The results reveal to there was significant low levels (p<0.005) of bile salts and phospholi
... Show MoreIraq has a range of small and large marshes, which can be divided into two groups, a group of marshes feeding water from the Tigris and Euphrates rivers, and a group of marshes fed by the seasonal valleys coming from the desert plateau and the aljazera plateau.
The marshes have go through major changes, some of them turning into industrial lakes to store the flood waters of the Tigris and Euphrates rivers. Others have been dried up and turned into agricultural land. Others have dried up and the water has been returned to them in less quantities than before.
The purpose of this research is to but light on the changes that have occurred in these marshes, with the mention of marshes turned into industrial lakes or agricultur
... Show MoreIn this work, production of silicon metal at high purity of 99% by using Iraqi–starting materials (Iraqi sand and plant coal)was reported, electric arc–furnaces assembly was manufactured inside, the graphite electrodes were made from graphite scrap, this system is operate to produce about 800 gm /6hr of silicon metal to meet the need for manufacturing silicon oils, resins, solar cells, and electronic parts. The procedure, equipments and analysis data were described as well.
Ceremony of the Koran vocabulary animate different connotations unique style patch on
smth not any method of Arabs, has been used used vocabulary and special Madza, he put
every single in place of installation so that if you do not put in place misfire meaning and
became Rkika method. Our goal in this research study a range of vocabulary in terms of the
implications and documenting the trial of the Hadith and sayings of the beneficiaries of Arab
scholars have different attitudes, linguists and interpreters and speakers and fundamentalists,
philosophers, and others.
Language is fundamental and important for the development of various skills especially in the kindergarten stage where the child begins to approach others and interact with them linguistically listen to them and make sentences to communicate his ideas to them and without the ability to talk and expression, the child's benefit of his experiences in the kindergarten remains limited.
And that children at any stage of early education are subject to different stages of linguistic development, and these stages are a fundamental feature in learning, especially for the skills of speaking, listening and reading, Therefore, the researcher chose the speaking skill the
... Show MoreThe following list comprises sixty-one species and subspecies of coccine¬llid beetles belonging to twenty-two genera distributed among six tribes in three subfamilies. All the species and subspecies have been recorded for Iraq. The categories have been arranged systematically according to Korschefsky's (1931) catalogue.
Research summary
Praise be to God, Lord of the worlds, and prayers and peace be upon the one who was the most eloquent of people in language and the most eloquent of them in eloquence, our Master Muhammad (peace and blessings of God be upon him).
To proceed... There is no doubt that many studies have preceded me in talking about chalk, each according to his own destination and view, and what I do not deny is that I benefited a lot from it, and it provided me with a lot of valuable information, and I liked to be one of those study pens, trying as much as possible To add something new and different in the study, far from similarity and repetition. Especially in the Abbasid study.
The babble in the Abbasid society was d
... Show MoreWorldwide attention is being focused on nanocrystalline zeolites and they are replacing conventional ones due to their pronounced potential in many fields. In this study, NaY zeolite has been prepared hydrothermally using sol –gel method and modified to the proton type by ion –exchange process. Characterization is made using X-ray diffraction (XRD), thermogravimetric analysis (TGA), Fourier transform infrared spectroscopy (FTIR), Atomic force microscopy (AFM), Brunauer –Emmet- Teller (BET) nitrogen adsorption method, Ammonia Temperature programmed desorption (NH3-TPD) and Scanning electron microscopy( SEM). The effect of aging time, silica to alumina ratio is studied and the results sh
... Show MoreThe importance of earnings quality begin increase in recent year . Particulary after collapse the big companies in U.S.A When the Stock Prices of this Companies negative impact after reporting of transitory & unrealized earnings in the iterim reports , in the same time took to this earnings as absis of Future Predictions .
Many of acadmic researchers discusses empirical measures that used to assessments of earnings quality from the perspective of decision usefulness that represent core of FASB's conceptual Framework , and to the economic – based definition of earnings , developed by (Hicks) in 1939.
Tise research attempt to test som of earnings quality measures in commercial
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