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 Current research aims to identify ( The effects of 4EX2 Model in Misconception of Chemical concepts and Higher Order Thinking for the Students of the Third grade average ) , To verify the objective of this research , the researchers added nul hypothesis following : There is no difference is statistically significant at the level of ( 0.05 ) between the average scores of students who studied 4EX2 Model and the average students who studied by using the Misconception of Chemical concepts and Higher Order Thinking test. The research was conducted on a sample of the average Third grade students in a Baghdad secretary for boys affiliated to the General Directorate for Educational in Baghdad Al – karkh 3 and for academic year ( 2015 – 2
... Show MoreThe study relied on data about the health sector in Iraq in 2006 in cooperation with the Ministry of Health and the Central Bureau of Statistics and Information Technology in 2007 Included the estimates of the population distribution of the Baghdad province and the country depending on the population distribution for 1997,evaluate the health sector which included health institutions, and health staff, and other health services. The research Aimis; Measurement an amount and size of the growth of health services (increase and decrease) and the compare of verified in Iraq and Baghdad, and evaluate the effectiveness of the distribution of supplies and health services (physical and human) of the size of the population distribution and
... Show Moreهذه الورقة البحثية تهدف الى مناقشة سبل تطوير التعليم العالي في العالم العربي والارتقاء به لخلق راسمال بشري وثقافي قادر على مواجهة تحديات العصر، فالتنمية الاقتصادية في العصر الحالي ما عادت تعتمد على المواد الاولية بل على القيمة الابداعية للانسان التي اصبحت اساسية في المنافسة الحالية بين الشعوب الانسانية و اصبح الفكر المبدع هو المنافس الحقيقي المهم حيث تصنع احدث الاجهزة الحديثة باحجام صغيرة ومواد اولية اقل
... Show MorePerformance measurement is considered one of the most important issues in
Measuring performance effectiveness in the educational institutions by maintaining balance among quantity measurable factors. They can be financial or non‐financial factors. Consequently they reflect decisive factors in the success of educational institutions and determining suitable standards and dimensions for their activities and giving it proportional importance. Adopting the idea of Balanced Score Card as one of the modern administrative techniques and methods by educational institutions assists in the development of administrative work, adjusting the performance in addition to achieving comprehensive standard and development of educational universit
... Show Moreالانسحاب الاجتماعي بغض النظر عن العوامل المسببة له قابل للعلاج حيث وضحت البحوث العلمية إمكانية الحد منه باستخدام أساليب تعديل السلوك .
وهو نمط سلوكي شائع لدى معظم الفئات ان لم يكن كل فئات الاعاقة ،وينتج هذا النمط السلوكي الانسحاب الاجتماعي عن عوامل عدة فاذا الطفل يعاني من تلف في الجهاز العصبي المركزي فان هذا التلف قد يحول دون قيام الطفل بالنشاطات المطلوبة للعلاج. توضح البحوث العلمية ام
... Show MoreIt was the most important weapons that were used during the long cultural war standing against Islam, it is interesting colonists Muslim women special attention, and directed to lure women rebellion against religion, and go out on their own teachings in this religion,