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.
تشهد الساحة الاعلامية في وقتنا الحاضر تطورات سريعة وبشكل متزايد سواء في طريقة صناعة الرسالة الاعلامية او اسلوب تقديمها وعرضها ،وفي ظل تعدد وتنوع وسائل الاعلام الجديد والزخم الاعلامي الذي يتعرض له المستخدم فيجد نفسه وسط كم هائل من الاخبار متعددة المصادر والاشكال ، فكيف له ان يميز بين المعلومة الصادقة والزائفة ؟ ومادرجة ثقته بتلك المعلومات والمواقع الالكترونية ؟ ويهدف البحث الى الكشف عن مدى توفر عناصر صناعة
... Show MoreAnhdralazuri of Yazour a village Ramle Palestine, from a religious family of Abu Mohammed Yazouri arrived in Egypt in the year (439 AH / 1036 AD), and was aimed from behind, returned him to his previous position to assume spend Ramle, Fasttaa a senior statesmen to provide Abu Muhammad Yazouri L. Caliph assuming start, Vtm him so, raising its standing and became MetwallyDiwan or caliph, in the year (441 AH / 1049 AD) was assigned the Chief Justice did not stop at that, but the era of his post of the ministry a year (442 AH / 1051 AD), having proven merit in every Matulah, The minister Yazouri of the powerful minister aspiring and employers pens won several titles did not collect it for one by the judiciary, advocacy and ministry granted C
... Show MoreIn recent years, the means of communication have achieved a great generality that made them occupy, in a short time, the first ranks among the most widely used social networks in the world, due to the many services and advantages offered by this network to its users. It has led to a leap in the field of visual communication, especially since it relies mainly on the image Its dimensions make it a means of communication and transfer of ideas and meanings between the peoples of the world, and it also allows the inclusion of digital advertising content using multimedia with a degree of professionalism in other social networks, which allowed the various segments of society the opportunity to invest this network in their businesses of differen
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The impact of religion in the character of the King Amenmhet I
1991-1961B.C.
This research try to show the influence of the religion in the character of King Amenmhet I , he entered the names of the gods in the installation of his names, because he aimed to the trust of fellows and to get the loyalty centers of worship, and deliberately enter the name of the god Amun in the composition of his name and make him the first god of the state, which covered all the gods of Egypt, after the merge with each other, such as the gods Re became the god Amun - Re or after he inherited the functions of some of the other recipes such as what happened with the god Min
هذا البحث يعنى بدراسة بعض المظاهر اللسانية التي اثارها فخر الدين الرازي في تفسيره الكبير المعروف ب(مفاتيح الغيب) والوقوف عندما يعرف في اللسانيات المعاصرة بالصفة الخطية للكلام وقد
وقد اثبت البحث ان الرازي اكد ما نسطلح عليه اليوم ب(الصفة الخطية للكلام) اي ان الدال ذو طبيعة سمعيه وانه يجري في الزمن وحده
Arab heritage have teem much of the literature value, written by evacuated, who had a legacy of linguistic great scientists, but the circumstances are unknown, did not write those books or authors emerge, chose to search for a book of those compositions, he did not write to him and his book emerge, fell hands a book (Altvsh in the language) to Abu Sufyan grammar, a fourth-century scientists, as it is Abu Sufyan grammar of scientists who rolled up the time their impact, and the cryptic revelations among the stars, preferring to stand on this book and its author, a statement of the most important grammatical aspects contained therein; to notch the curtain for this world, and his book (Altvsh in strewn language and Mnzawmha and express the
... Show MoreThe early childhood is a dangerous period for the development of children
in their present and future life . It is important to design programs for the preschool
period .
These programs are relatd to the childs Personality and its integration .
The most effective stories and attractive programs for the child is the objective
stories which can develop his self-canfidence . Therefore the kindergarten
should participate in developing the childs personality and experience
because it is the most effective institute in the childs life .
The present study aims at finding out the effect of the narrative program in
the kindergartens . This has been done by investigating the truth of a number
of hypotheses to measure
Araştırmamın adı: Türkçe'de –madan, -meden Ulaç Ekinin Yazılışı ve Kullanılışıdır.
Ulaçlar, kişi ve zaman kavramı olmadan temel cümlenin yada yan cümlenin yüklemini niteleyen, cümlede genellikle zarf tümleci olarak görev yapan fiilimsilerdir. İkinci bir görevleri yardımcı fiillerle birlikte kullanılarak birleşik fiiller kurmak olan ulaçlar, cümlede bağlaç görevinde kullanılabilirler, ve birleşik cümleler kurabilirler. Bazı ulaç ekleri zarf, edat gibi kalıcı sözcük yapımında da kullanılırlar.
Bu araştırmada Orhun Türkçesi'nde başlayıp Türkiye Türkçesine kadar uzanan tarihi dönemlere ait eserlerden –m
... Show MorePraise be to God, who is by His Power, righteous is done, and by His help to slaves who He likes, and God bless our Prophet Muhammad envoy mercy to the worlds, and upon his family and the good mates until Doomsday.After:
The fact that cursing is the far distance and expulsion from the mercy of God, curse has been proven by him - peace be upon him - for the many varieties in the Sunnah, with indication of a permit cursing the insurgents from the people of Qibla, either saying - peace be upon him -: (the believer never be as a curser ...), what is meant by those who do not deserve damnation of those not cursed God and His Messenger, and for this we must remove words cursing from the Dictionary of our words following the examp
... Show MoreThis search aims to meditate Divan of Hazem Al-Qirtagni his incomplete contiguous and non-contiguous naturalizations are investigated through two interrelated sections, the first is contiguous deficient naturalization and the analysis of phonemic symmetry in the light of syntactic syntax, phonemic (partial) symmetry and semantic difference