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.
تزداد أهمية وجود اللغة العربية على الشبكات الحاسوبية مع توجه المجتمع نحو مجتمع المعلومات, ونحو الاقتصاد المبني على المعرفة. ويصطلح عالمياً على هذا الوجود بكلمة المحتوى, فكيف يمكن أن نزيده
لمحة عن حالة حقوق الانسان في كوردستان العراق
This research aims to present a range of views and beliefs about the climate that have prevailed spontaneously in the Iraqi society and, whether agricultural or Bedouin communities and even popular communities within cities.
عاش البيروني في القرن الرابع الهجري الذي كان يمثل مثاراً للصراعات السياسية والفكرية، ومن خلال هذه الأوضاع المتأزمة برز البيروني كعلم من اعلام هذا القرن، ومن أبرز مفكري الحضارة العربية الاسلامية فنجده كتب في الرياضيات
This is an empirical investigation of the tribal power in Iraq and its consequences on the socio-political system. A theoretical background concerning thestate kinship, tribe and tribal involvement in politics has been displayed with example of tribal power over people within the social context. Socio-anthropological method of data collection has been used, including a semi-structured interview with a sample of 120 correspondents. The outcome revealed that the feeble and corrupted state (government) play a vital role in encouraging the tribe to be dominant. The people of Iraq are clinging to the tribe regardless of whether they believe in it or not. Although they are aware that the tribe is a pre-state organisation and marred shape of ci
... Show MoreHarold Pinter was one of the most important dramatists in the modern and the
contemporary age. Pinter presented his own dramatic realm in which he turns the theatre into
a moral institution. He employed the elements of several schools of drama and manipulated
them in order to deliver his ethical messages emphasizing the necessity to regain and renew
the world's morality in order to face the political and social injustices committed against
humanity. His writings developed over more than fifty years in style, techniques and his
interests. However, his main concern was his social and political satire.
ملخص البحث
العولمة ظاهرة اقتصادية سياسية اجتماعية لها انعكاساتها المختلفة على المجتمعات وعلى منظمات الأعمال في مختلف دول العالم، هذه الظاهرة أدت إلى المزيد من النتائج التي زادت منظمات الأعمال في الدول الغنية غناً وزادت منظمات الأعمال في دول العالم الثالث فقر، وقد ترتب على ذلك نتائج ايجابية لدى المجتمعات الغربية والمؤتلفة معها بسبب سيطرة منظمات الأعمال في تلك الدول على الأسواق في البلدان الن
... Show MoreReduction has been linked visually in art since man began making functional and aesthetic forms, and this beginning can be identified with cave paintings. Reduction is one of the clearest indications of intellectual presence in aesthetic experience. Modernism was greatly supported by the great transformations that the intellectual movement witnessed in the world in general and in Europe in particular. There, and their transfer of European artistic experiences, and the reflection of this influence in their aesthetic sculptures, and for this reason the researchers find that the study of the aesthetic references of the reductive forms in the Iraqi sculptural experience represents a great importance in the study of the history of contemporar
... Show MoreAccording to Bowens Family systems theory self – differentiation defiance as a
construct that consists of two interrelated abilities : the first is an intrapsychic
ability to distinguish between the thoughts and feelings , and an inter personal
ability to maintain connections with others while achieving an autonomous self .
The present research concerned in testing the hypothesis of marital similarity
(people married persons with the same level of self – differentiation).
The present research aimed to:
1. Measures self – differentiation of university officers .
2. Measures self - differentiation of sample husbands' .
3. Measures self - differentiation of sample wives .
4. Acquaint to the relation betwe
In her poetry, Carol Ann Duffy looks into the concerns of the disregarded and humiliated people. Approaching facts fearlessly and disclosing realities in a way highly characteristic of her, she establishes the world newly and reframes it honestly. This research shows how Duffy reframes the world in her own peculiar terms, starting with her own creative use of the language, in particular, when the forms of things of the world are distorted, thus our perception of things will be reframed too.
As regards relations among people, the research elucidates how Duffy’s strained characters abandon real life and reframe an eccentric way of living, while respecting faith, wherein Duffy notices that religious rituals confine the intellect, she r