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 researcher highlighted in his research on an important subject that people need, which is the excuse of ignorance in Islamic law. , As the flag of light and ignorance of darkness. Then the researcher lameness of the reasons for research in this subject as it is one of the assets that should be practiced by the ruler and the judge and the mufti and the diligent and jurisprudent, but the public should identify the issues that ignore ignorance and issues that are not excused even if claimed ignorance.
Then the researcher concluded the most important results, and recommendations that he wanted to set scientific rules for students of science and Muslims in general, to follow the issues of legitimacy and learn its provisions and i
دف البحث إلى قياس الشخصية الاستغلالية لدى طلبة الجامعة على وفق متغيرات: الجنس والتخصص والمرحلة الدراسية ، تكونت عينة البحث من (200) طالباً وطالبة من طلبة جامعة بغداد، قامت الباحثة ببناء مقياس الشخصية الاستغلالية وبعد تطبيقه على العينة وتحليل البيانات بالوسائل الاحصائية المناسبة ، اظهرت نتائج البحث عن شيوع الشخصية الاستغلالية لدى الطلبة ، وان الذكور لديهم شخصية استغلالية اكثر موازنة بالاناث كما اظهرت نتائج ا
... Show Moreيعد التحليل البلاغي تركيبيا وبيانيا من الآليات الكاشفة عن الدلالات العميقة المتولّدة جراء علاقات البنية السطحية ، مكونة نسقاً دلالياً متماسكاً ومشحوناً بتكثيف معنوي للصور البلاغية المنسوجة في نص القصيدة، والتي تفتح للمتلقي نافذة التشكيل المتخيل لحال الشعب وحاكمه ، والعلاقة القائمة بينهما في القصيدة ، إذ نسج الشاعر علائقية متنامية الدلالة بين أجزاء قصيدته ووحداتها ؛ لتكون كلاً واحداً ناقلاً المتلقي لواق
... Show Moreدور المواد النانوية في إعادة تصنيف تكاليف المنتج الصناعي الحديث
حروف الجر هي حروف إضافة وروابط تدخل على الأسماء فقط ،فهي من علاماته فتعطيه حكم الجر؛ وبدخولها على الأسماء تجمع معانٍ للكلمات المتفرقة والمتناثرة في جمل متناسقة مفهومة في ذهن القارئ والمتلقي وتوصل معاني الافعال إلى الأسماء التي لا تستطيع الوصول إلى مفاعيلها، وهذا يدل على أن حروف الجر حروف عاملة وإن كان بعضها يأتي زائداً ،ولكل حرف من هذه الحروف معانٍ ودلالات قد تنفرد بها أو تشترك مع الحروف الأُخر فتضفي هذا الم
... Show MoreThis search in the virtues of the daughter of the Prophet Muhammad, to read on their boards want to recount loving and faithful), as stated in the introduction to the author, Abdullah Bin Ibrahim Al-Mirghani (D. 1207 H.) to give reasons in writing the manuscript, which was of an introduction and three chapters and a conclusion was the first in the door thanks to the great lady and on her birthday and her marriage and her death and subsequent events and the third in her them prayers and then the finale which was in love with the Prophet and calling for God to pardon and forgiveness and a good end. I was interested in this manuscript by Mirghani, Hadith and all accounts in reference to the virtues of the great lady to examine a manuscript
... Show MoreThe process of identifying the region is not an easy process when compared with other operations within the attribute or similarity. It is also not difficult if the process of identifying the region is based on the standard and standard indicators in its calculation. The latter requires the availability of numerical and relative data for the data of each case Any indicator or measure is included in the legal process