Background: preparation of root canals is an important step in root canal treatment. Mechanical instrumentation of root canals cause an irregular layer of debris, known as the smear layer. As a result, several studies reported that preferring the removal of the smear layer. Objective: To study the influence of the energy (100 mJ) of Erbium, Chromium: Yttrium Scandium Gallium Garnet (Er,Cr:YSGG) laser at short pulse duration (60 μs) on smear layer removal of apical third after using Photon induced photoacoustic streaming technique. Materials and methods: Eighteen straight single-rooted mandibular premolars were used. The roots length were uniform to 14mm from the anatomic apex and instrumented using Protaper Gold Rotary NiTi file system to size 40 taper 0.06. Er,Cr:YSGG pulsed laser (waterlase iplus Biolase, CA, USA) 2780 nm was used at short pulse duration (60 μs, 5 Hz ,air and water off) delivered by MD/iplus Glass Tips (MZ6) 600 μm in diameter, length=6 mm, calibration factor= 1.00. Ultrasonic activator ENDO1 (Guilin Woodpecker Medical Instrument Co., Ltd.china) was used with Ultrasonic activator tip ED98 (25#, 2% taper, 18.5mm) (Guilin Woodpecker Medical Instrument Co., Ltd.china). The samples were arbitrarily divided into three groups (n=6) and used as follows: (A) conventional irrigation with 5 ml of 17 % EDTA, (B) passive ultrasonic irrigation with 5 ml of 17 % EDTA, (C) Er,Cr:YSGG induced photoacoustic streaming with 5 ml of 17 % EDTA. After final irrigation with normal saline and drying, the roots were painted with nail varnish externally, and 2% methylene blue dye injected into canal until the canal filled with dye. The tooth was splitted at the fourth millimeters from root apex with a diamond disc representing the apical third. Picture was taken by Professional Digital SLR camera (Nikon D7100, Nikon Corporation, Thailand) with 40X magnification. The dye penetration was measured by using analytical software (measure picture CAD-KAS Kessler Germany). ANOVA test was used to analyse repeated measure mean between tested concentration (5.25% NaOCL, 17% EDTA) and control. Data was expressed as mean±SD. LSD (Least Significant Difference) test was used to calculate the significant differences between tested mean. Results: The mean values of the percentage of dye penetration area in two experimental groups was higher than the control group, as the follow (20.79±1.15control, 34.5453±0.45 ultrasonic group, 85.9804±2.69 Er,Cr.YSGG+17%EDTA at 0.5 W). The Percentage of dye penetration in Er,Cr:YSGG laser induced photoacoustic streaming with 17% EDTA was significantly high (P value 0.001), followed by ultrasonic activated group, while control group result in less Percentage of dye penetration than both study groups. Conclusion: In this study, we concluded that Er,Cr:YSGG pulsed laser (0.5 W,5 Hz , air and water off) at short pulse duration (60 μs) with 17% EDTA using PIPS technique for activation of irrigant in endodontic treatment give better result than ultrasonic activation in smear layer removal
السياسة الداخلية لعراق ما بعد الانتخابات 2010 دراسة في الثوابت والمتغيرات
اسباب تفرد استخدام خط النسخ في تصميم الحروف الطباعية
في تعزيز بيئة الانتاج الرشيق استخدام اسلوب S -5
Background: Acne vulgaris is one of the top three most commonly encountered dermatological problems worldwide in both primary and secondary care. Human keratinocytes express functional TLR2 heterodimers. An increased expression of TLR2 was detected in the epidermis of inflammatory acne lesions, as observed in normal skin; the expression level increased with the degree of differentiation of the keratinocytes. TLR2 expression is upregulated in inflammatory acne lesions and induced by C. acnes. The current study conducted to assess the oral isotretinion treatment effect on the acne vulgaris patients by evaluated the Toll Like Receptor 2 as a major immune system marker in Acne vulgaris immune re
... Show MoreThe existing study aimed to assess four soil moisture sensors’ capacitive (WH51 and SKU: S EN0193) and resistive (Yl69 and IC Station) abilities, which are affordable and medium-priced for their accuracy in six common soil types in the central region of Iraq. The readings’ calibration for the soil moisture sensor devices continued through two gravimetric methods. The first depended on the protocols’ database, while the second was the traditional calibration method. The second method recorded the lowest analysis error compared with the first. The moderate-cost sensor WH51 showed the lowest standard error (SE), MAD , and RMSE and the highest R² in both methods. The performance accuracy of WH51 was close to readings shown by the manufac
... Show MoreThe study aims to identify the extent of the availability of administrative empowerment and the implementation of remote supervision in relation to two variables with respect to the employees of the Saudi Ministry of Education. The study included (456) male and female supervisors. The questionnaire has been administrated to collected data related to the research aims. The results indicated that both the extent of the availability of administrative empowerment and the implementation of remote supervision is of an average degree. There is a significant correlation relationship (p<0.05) between administrative empowerment and remote supervision of the educational supervisors of the Saudi Ministry of Education. The research recommends that
... Show More: تفرض مرحلة إعادة بناء الدولة أو مرحلة بناء الدولة حالتين متقاربتين، لكن تختلف تجربة كل منهما عن األخرى، ففي الحالة األولى نعني بها أن دولة ما متكاملة المقومات سواء القانونية أو السياسية أو االقتصادية، وتمتلك هذه الدولة الشرعية القانونية واالعتراف الدولي، لكن تتعرض هذه الدولة لألزمة سواء كانت ثورة أو انقالب أو احتالل، وإلى السقوط ونهاية نظامها السياسي القانوني ومن ثم إعادة بناء الدولة ومنظومتها السياسية..
... Show Moreمرت العلاقات المصرية – الامريكية بمنعطفات مهمة كان لها تاثيرها الكبير في مسار تلك العلاقات ولعل اهمها حرب حزيران 1967 و حرب تشرين الثاني 1973 ،الا ان تلك العلاقات اخذت منعطفا مختلفاً خلال عهد الرئيس المصري انور السادات واستمرت تلك العلاقات حتى عهد الرئيس المصري حسني مبارك وشملت مختلف المجالات السياسية والاقتصادية والعسكرية والامنية ،بل وصلت العلاقة بين البلدين الى حد الشراكة..ومهما قيل عن تحسن العلاقات المصر
... Show Moreنزع السلاح بعد انتهاء الحرب الباردة " دراسة نقدية"
The issue of the research lies in the non-representation of the models developed for the communication process in the interaction and networking processes through social media, as the research sought to build a network model of communication according to the specific data and features of social media platforms in order to reach a special generalization to understand how the process of networking operates in cyberspace.
The researcher followed the analytical survey approach as she described the communication models outwardly in order to be able to build a networked communication model that represents the flow of post-reactive communication. Therefore, it has been named "Nebula - Sadeem" after the concept of post-space and cosmic g
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