Laser etching may be an alternative to acid etching of enamel and dentin. Several characteristics of irradiated dental hard tissues have been considered advantageous, microscopically rough surfaces without demineralization, open dentinal tubules without smear layer production and dentin surface sterilization. The aim of this study is to determine and compare histology the microleakage in class V cavity restored with a light cured composite after conditioning the samples(tooth surface) with 1-acid etching, 2-Q-switched Nd:YAG Laser etching and finally 3- acid and laser etching. Materials and methods: Twenty four non carious human extracted teeth were used in this study. The samples were equally grouped into four groups of six teeth each. A class V cavity was prepared. In group I, tooth surface was etched with a 37% phosphoric acid gel. In group II, the tooth surface was conditioned using a pulsed Nd:YAG Laser alone with a wavelength of 532 nm. The parameters were of pulse energy 60 mJ, pulse repetition rate 6Hz and energy density was 0.48 J/cm2. In group III, the tooth surface was treated with Nd: YAG Laser and then was etched with phosphoric acid. In group IV, the surface was treated with 37% phosphoric acid then irradiated with Nd: YAG Laser; with the same parameters and concentration mentioned in group I and II. The samples immersed in 1% basic fuschin dye to mimic the normal stains in oral cavity and the sections were examined by a stereomicroscope and the readings were scored. Results: The results showed that group IV, in which the surface was treated with 37% phosphoric acid and then irradiated with Nd: YAG Laser) recorded the least microleakage of the four groups, where group III, in which the tooth surface was treated with Nd: YAG Laser and then was etched with phosphoric acid)recorded reasonable results better than group I (group I tooth surface was etched with a 37% phosphoric acid gel) or group II , in which the tooth surface was conditioned using a pulsed Nd:YAG Laser alone) Conclusion: The use of Q-switched Nd:YAG laser in etching the tooth surface was so effective that it can be used in treating or conditioning the tooth surface to enhance bonding and the best parameters among the tested samples were pulse energy of 60mJ, pulse repetition rate of 6Hz and energy density 0.48 J/cm2.
The organization and development of the irrigation system and agrarian reform in Iraq had an impact on the diversity of its methods and uses.
The Arab woman expressed the life of oppression that she suffers from in her masculine environment, as she expressed her linguistic abilities with eloquence and intelligence, as she did not neglect philosophy, wisdom,
كان لسياسات االحتالل دور بارز في فشل مشروع إعادة بناء الدولة في افغانستان، وفي الوقت نفسه تتحمل دول االحتالل المسؤ و لية الكاملة عن بعض هذه ً كبي ارً السياسات مثل عدم التخطيط الجيد لمرحلة االحتالل وإعادة بناء الدول ة، ثم إن جزءا من فشل هذه السياسات يرجع الى البيئتين المحلية واإلقليمية ، كذلك كان للخبرة السياسية والدستورية وللواقع االجتماعي الثقافي األفغاني تأثيرهما المهم في قدرة المجتمع األفغاني ً على قبول
... Show MoreGaining economic policy of exceptional importance in severe unilateral Iraqi economy such as the economy, as oil revenues constitute the center of gravity in the internal and external balances, Economic policy have seen in Iraq beyond 2003 in absentia economic strategic vision and failure in the application of policies to achieve economic development, as there was a disconnect and lack of integration and coordination between macro policies of monetary policy and fiscal policy, especially as if they were floating two policies are not linked by a link
This research deals with the use of a number of statistical methods, such as the kernel method, watershed, histogram, and cubic spline, to improve the contrast of digital images. The results obtained according to the RSME and NCC standards have proven that the spline method is the most accurate in the results compared to other statistical methods.
Alternative distribution to estimate the Dose – Response model in bioassay excrement
This research concern to study five different distribution (Probit , Logistic, Arc sine , extreme value , One hit ), to estimate dose –response model by using m.l.e and probit method This is done by determining different weights in each distribution in addition find all particular statistics for vital model .
مشكلة البحث :
إن القرآن الكريم هو النور المبين والذكر الحكيم يحتوي على الغاية الأسمى التي تهدف اليها الإنسانية ، فهو روح التربية الإسلامية وهو المنهج القديم الذي تستمد منه فلسفتنا التربوية واتجاهاتها ، (الزوبعي ، 1974: 18)
إن الدين الإسلامي هو نظام الهي
... Show Moreيتركز محور مشكلة البحث الحالي حول مفاهيم أساسية تعكس مكامن القوة في الشخصية الإنسانية وما لها من دور مؤثر على الواقع النفسي والمادي للفرد عموماً وهذه المفاهيم هي صلابة الشخصية، وتقدير الذات,ويتحدد مفهوم الصلابة من خلال مظاهر الشخصية وأسلوبها الذي تتميز به في التعامل مع الواقع وكيفية إدراكها وما تتمتع به من خبرات نفسية وتجارب حياتية داخلية تعكس مدى الوعي بالمستجدات الموقفية التي تصادفها
... Show MorePsychological Counseling Services occupies a high position in the developed countries and that for its psychologist services for different sectors of the community members, and has been popularized until recently the wrong concept of the effect, that the psychological service is provided only to the owners of behavior is normal only, Vantage him neglect to provide psychological services a large segment of the community members who are in dire need of these services.
The counseling service is part of a global social movement seeking to emphasize the quality of life of the human and the emphasis on the value and dignity and the need to live a quiet lif
... Show MoreThis study deals with the region of the Babylon governorate in Iraq during the Proto-Literate and Early Dynastic periods. It is the region of the well- known ancient capital Babylon. The earlier period includes Late Uruk, Jamdat nasr, and the first epoch of the Early Dynastic period. The latter includes the second and third epochs of the Early Dynastic period. The both periods had lasted more than one thousand years (3500-2334 BC