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
The main objective of the central bank is to achieve price stability and target in fractionates. Therefore, the bank sought to use modern tools and policies in order to reduce the negative effects of the accumulation of foreign reserves represented by monetary sterilization, similar to developed and developing countries alike, but with different available tools that are possible and imposed by the local financial and monetary environments, such as the window for buying and selling foreign currency, open market operations and deposit facilities. And lending existing. Because any in crease in the monetary base resulting from the accumulation of foreign reserves will affect price stability directly due to the consumer nature of the
... Show More: The Aluminium (Al) material emerged as a plasmonic material in the wavelength ranges from the ultraviolet to the visible bands in different on-chip plasmonic applications. In this paper, we demonstrate the effect of using Al on the electromagnetic (EM) field distribution of a compact hybrid plasmonic waveguide (HPW) acting as a polarization rotator. We compare the performance of Al with other familiar metals that are widely used as plasmonic materials, which are Silver (Ag) and Gold (Au). Furthermore, we study the effect of reducing the geometrical dimensions of the used materials on the EM field distributions inside the HPW and, consequently, on the efficiency of the polarization rotation. We perform the study based o
... Show MoreBackground: The aim of this study was to evaluate the push-out bond strength of four different obturation materials to intraradicular dentin and to determine the failure mode. Materials and method: forty straight palatal roots of the maxillary first molars teeth were used in this study, the roots were instrumented using crown down technique and rotary EndoSequence system, the roots were randomly divided into four groups according to the materials used for obturation (n=10).Group (1): AH Plus sealer and gutta-percha. Group (2): Activ GP glass ionomer sealer and Activ GP gutta-percha (Activ GP system). Group (3): Bioceramic sealer and Bioceramic gutta-percha. Group (4): GuttaFlow2 sealer and gutta-percha. For all groups single cone obturatio
... Show MoreHeat transfer process and fluid flow in a solar chimney used for natural ventilation are investigated numerically in the present work. Solar chimney was tested by selecting different positions of absorber namely: at the back side, front side, and at the middle of the air gap. CFD analysis based on finite volume method is used to predict the thermal performance, and air flow in two dimensional solar chimney under unsteady state condition, to identify the effect of different parameters such as solar radiation. Results show that a solar chimney with absorber at the middle of the air gap gives better ventilation performance. A comparison between the numerical and previous experimental results shows fair agreement.
Background: Coated aesthetic archwires are currently the existing solutions for the esthetic problem, but the color of these archwires tends to change overtime. This study was aimed to evaluate the color stability of different types of esthetic archwires from four different companies at different time periods after immersion of two different staining drinks which are tea and Pepsi cola. Materials and methods: 48 specimens were prepared, each specimen contains 10 aesthetic archwires; and were divided according to type of solution into two groups: A (tea) &B (Pepsi cola); each group contained 24 specimens (12 specimens were immersed in the staining solution as 4 specimens for each time intervals and 12 specimens were immersed in distilled wa
... Show MoreTitanium alloy surface properties have an essential role in the interaction of dental implants with bone, and alteration of the surface of the implant could improve osseointegration. This study was designed to investigate the effect of different heat treatment temperatures on titanium alloy surface properties for dental implants. The effect of different temperatures of heat treatment (750°C, 850°C, 950°C and 1050°C) were investigated on the surface topography, surface chemistry, titanium oxide layer thickness, blood contact angle, & blood drop diameter of titanium alloy. The disks were prepared from titanium alloy (Ti-6Al-4V) and the samples were divided into five groups depending on the different temperatures of heat treatment. The hea
... Show MoreThis study is concerned with a survey of seven species belonging to seven genera under two families and two orders found in some different areas of the Tigris River, especially since these areas have not been surveyed for a long time, and an attempt to identify the existing species at the present time after the recent water scarcity of the Tigris and Euphrates rivers and all water bodies interior of Iraq and the impact of this scarcity on the fish diversity found in some areas of the Tigris River in Baghdad.
Gas hydrate formation poses a significant threat to the production, processing, and transportation of natural gas. Accurate predictions of gas hydrate equilibrium conditions are essential for designing the gas production systems at safe operating conditions and mitigating the problems caused by hydrates formation. A new hydrate correlation for predicting gas hydrate equilibrium conditions was obtained for different gas mixtures containing methane, nitrogen and carbon dioxide. The new correlation is proposed for a pressure range of 1.7-330 MPa, a temperature range of 273-320 K, and for gas mixtures with specific gravity range of 0.553 to 1. The nonlinear regression technique was applie
<span lang="EN-US">Diabetes is one of the deadliest diseases in the world that can lead to stroke, blindness, organ failure, and amputation of lower limbs. Researches state that diabetes can be controlled if it is detected at an early stage. Scientists are becoming more interested in classification algorithms in diagnosing diseases. In this study, we have analyzed the performance of five classification algorithms namely naïve Bayes, support vector machine, multi layer perceptron artificial neural network, decision tree, and random forest using diabetes dataset that contains the information of 2000 female patients. Various metrics were applied in evaluating the performance of the classifiers such as precision, area under the c
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