Background: Apicoectomy and retrograde filling is indicated when conventional endodontic treatment is impossible or failed to achieve apical seal. The aim of this study was to evaluate the effect of ER: YAG laser on apical microleakage. Materials and Methods: Sixty extracted single-rooted teeth were used in this study. The roots were divided into six groups. Group 1: apicoectomy by fissure bur, and apical cavities prepared by round bur, then cavities were filled with MTA. Group 2: the roots preparations and fillings were the same as group 1, then the apical areas were treated by Er:YAG Laser. Group 3: apicoectomy by fissure bur, and apical cavities prepared by ultrasound retrotip and cavities were filled with MTA. Group 4: the roots preparations and fillings were the same as group 3, then the apical areas were treated by Er:YAG Laser. Group 5: the roots obturation with gutta percha, then the apices were resected using Er:YAG Laser. Group 6: the roots apices were resected with Er:YAG Laser, then the canals were obturates with gutta percha. Apical microleakage was measured by methylene blue dye penetration technique. Results: Significant difference between the groups. Group 1 shows the best apical seal, while group 5 shows the worse apical sealing ability. Conclusion: Apicoectomy by bur is better than apicoectomy by laser, and apical cavity prepared by bur is better than prepared by US. The use of ER: YAG laser in apicoectomy is preferred to be done before obturation of the root canal with gutta percha.
Monetary sterilization policies are one of the modern trends of monetary policy in rentier countries, specifically to confront the positive shocks in foreign assets flowing into the national economy and the impact of these shocks on monetary and real variables. And that the Central Bank contains these emergency increases in foreign exchange with the aim of avoiding the impact of this increase on the official local currency through its three main monetary tools, which are the rediscount rate, the legal reserve, and open market operations. As well as the relationship between the central bank and the objective of external balance, which is reflected in the balance of payments balance, the central bank resorts to managing the exchange rate
... Show MoreThe current research aims to know the effect of Needham's constructivist model on the achievement of third-year students in the Life Sciences Department in the teaching methods subject. To achieve the research objectives, the experimental method was followed for the experimental and control groups with dimensional measurement of the achievement variable of the teaching methods subject. The research sample included (62) students in the third year of the Life Sciences Department, distributed into two equal groups in the variables (self-assessment of learning methods - chronological age in years - intelligence level - previous information). To measure the level of students' achievement, an achievement test was constructed consisting of (40) te
... Show MoreBackground and objectives: Whether to use a cold scalpel or laser surgery to remove a lesion in the skin of the craniofacial area is the main question the surgeon asks him- or herself to do. The study tried to extend the literature with data that may help the surgeons to choose the right method. Methods: Thirty patients with intra- and extraoral craniofacial skin lesions managed by Carbone dioxide (CO2) laser surgery. Results: The most common type of lesion treated was melanocytic nevi (15 patients; 50%). Conclusion: The main complication of CO2 laser surgery is the remaining permanent hypopigmentation of the treated area; however, the CO2 laser has many advantages (especially at the time of surgery) making it a good choice for the manageme
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We observed strong nonlinear absorption in the CdS nanoparticles of dimension in the range 50-100 nm when irradiant with femtosecond pulsed laser at 800 nm and 120 GW/cm 2 irradiance intensity. The repetition rate and average power were 250 kHz and
The tourism industry, with its two sides (recreational and religious), is one of the important investment fields in Iraq, it is represented Iraq as the second economic source after the oil sector. So a need for serious efforts to develop the tourism sector and maintain its sustainability. This paper will be one of the important contributions in this field; the paper aims to explore the extent of the impact of the sustainable strategy on the level of overall performance in the Iraqi tourism sector. The field of research was some Iraqi tourist institutions at Iraqi tourism, Which covers the field of study on the one side, and can be studied on the other side, for the developing study methodology and organizing its main parts, the research pap
... Show MoreThis study focusses on the effect of using ICA transform on the classification accuracy of satellite images using the maximum likelihood classifier. The study area represents an agricultural area north of the capital Baghdad - Iraq, as it was captured by the Landsat 8 satellite on 12 January 2021, where the bands of the OLI sensor were used. A field visit was made to a variety of classes that represent the landcover of the study area and the geographical location of these classes was recorded. Gaussian, Kurtosis, and LogCosh kernels were used to perform the ICA transform of the OLI Landsat 8 image. Different training sets were made for each of the ICA and Landsat 8 images separately that used in the classification phase, and used to calcula
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HR Ghanim, GA Abdulhassan, International Journal of Early Childhood Special Education, 2022
This research studies the effect of adding micro, nano and hybrid by ratio (1:1) of (Al2O3,TiO2) to epoxy resin on thermal conductivity before and after immersion in HCl acid for (14 day) with normality (0.3 N) at weight fraction (0.02, 0.04, 0.06, 0.08) and thickness (6mm). The results of thermal conductivity reveled that epoxy reinforced by (Al2O3) and mixture (TiO2+Al2O3) increases with increasing the weight fraction, but the thermal conductivity (k) a values for micro and Nano (TiO2) decrease with increasing the weight fraction of reinforced, while the immersion in acidic solution (HCl) that the (k) values after immersion more than the value in before immersion.
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Scorpions and spiders belong to the class Arachnida in phylum Arthropoda. Scorpions are easily distinguished by median eyes on obvious the center of the carapace and have one pair, and lateral eyes have 2-8 in some species. Scorpions do not have good eyesight so the median eyes have always been simple and they are more sensitive than the lateral pairs. They have anterior median eyes (AME) with narrow field of view and pairs of lateral eyes (LE) with more sensitivity and response to light. Family Buthidae have 2-6 lateral eyes in Compsobuthus Mesobuthus, Hottentotta, while Vaejovidae, Chactidae and Chaerilidae have 2 pairs of lateral eyes. In addition, 3 pairs are found in Orthochirus and Androctonus. Spiders have six eyes in family Pholicid
... Show MoreThe present study designed to determine the ethanolic extract of Cyperus rotundus on Liver in Albino Male Mice . In the present study 18 Male mice were used they divided into six groups ( 1st group consedered control group , 2nd group injected by 250 mg/ml from extract , 3th group injected by 300 mg/ml from extract , 4th group injected by 350 mg/ml from extract , 5th group injected by 400 mg/ml from extract and the 6th group injected by 450 mg/ml from extract ) . the expermint lasted for two days and the doses gived by intraperitonial injection . showed from the study results that ethanolic extract for Cyperus rotundus have negative effect on Liver tissue in 250 , 300 , 350 mg/ml concentrations when comparsion with control group . the re
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