Background: Enterococcus faecalis (E. faecalis) is a prototypical resistant bacterium in root canal infections and a leading cause of endodontic treatment failure. German chamomile (Matricaria chamomilla) flower extract has been used as a traditional medicine to treat infections. The aim of this study was to investigate the antimicrobial efficacy of chamomile extract on the removal of E. faecalis root canal biofilm. Materials and Methods: Chamomile flower extract was prepared and subjected to detailed chemical analysis. For the in vitro biofilm model, human mandibular premolars (n=48) with 18-20mm working length were used. Root canal preparation was performed using the ProTaper® Next system. Each sample was split longitudinally and reassembled within a pre-prepared silicone matrix, and a mature E. faecalis biofilm was grown for seven days. Samples were randomised into four groups (n=12 for each arm) based on the type of irrigant protocol comprising normal saline, 3% sodium hypochlorite (NaOCl), dual irrigation with 17% ethylenediaminetetraacetic acid (EDTA) and 3% NaOCl, and chamomile extract. After irrigation, residual biofilms were measured in (n=9/group) using densiometric measurements. Observational analysis of residual biofilm was performed in (n=3/group) using Scanning Electron Microscopy (SEM). Results: Phytochemical investigations showed that chamomile extract is rich in antimicrobial components such as flavonoids, polyphenolic compounds, tannins, and others. Spectrophotometry analysis showed a statistically significant difference between the normal saline group with mean optical density (OD)= 0.63044; ±0.106 and each of EDTA and NaOCl group (mean OD=0.35922; ±0.091), chamomile group (mean OD=0.37611; ±0.106) at p<0.001, and the NaOCl group (mean OD=0.46344; ±0.096) at p<0.01. No statistically significant difference between chamomile group and NaOCl and the dual EDTA and NaOCl irrigation protocol. SEM images showed removal of E. faecalis biofilm and smear layer was in the order: dual EDTA and NaOCl irrigation>chamomile extract>NaOCl. Conclusions: Chamomile flower extract has an apparent removal efficacy of E. faecalis biofilm from root canals. It may be a promising antimicrobial material to be used as a natural endodontic irrigation solution.
In this research, porous silicon (PS) prepared by anodization etching on surface of single crystalline p-type Si wafer, then Gold nanoparticle (AuNPs) prepared by pulsed laser ablation in liquid. NPs deposited on PS layer by drop casting. The morphology of PS, AuNPs and AuNPs/PS samples were examined by AFM. The crystallization of this sample was characterized by X-ray diffraction (XRD). The electrical properties and sensitivity to CO2 gas were investigated to Al/AuNPs/PS/c-Si/Al, we found that AuNPs plays crucial role to enhance this properties.
A genetic algorithm model coupled with artificial neural network model was developed to find the optimal values of upstream, downstream cutoff lengths, length of floor and length of downstream protection required for a hydraulic structure. These were obtained for a given maximum difference head, depth of impervious layer and degree of anisotropy. The objective function to be minimized was the cost function with relative cost coefficients for the different dimensions obtained. Constraints used were those that satisfy a factor of safety of 2 against uplift pressure failure and 3 against piping failure.
Different cases reaching 1200 were modeled and analyzed using geo-studio modeling, with different values of input variables. The soil wa
This research presents a method of using MATLAB in analyzing a nonhomogeneous soil (Gibson-type) by
estimating the displacements and stresses under the strip footing during applied incremental loading
sequences. This paper presents a two-dimensional finite element method. In this method, the soil is divided into a number of triangle elements. A model soil (Gibson-type) with linearly increasing modulus of elasticity with depth is presented. The influences of modulus of elasticity, incremental loading, width of footing, and depth of footing are considered in this paper. The results are compared with authors' conclusions of previous studies.
The research aims to use a new technology for industrial water concentrating that contains poisonous metals and recovery quantities from pure water. Therefore, the technology investigated is the forward osmosis process (FO). It is a new process that use membranes available commercial and this process distinguishes by its low cost compared to other process. Sodium chloride (NaCl) was used as draw solution to extract water from poisonous metals solution. The driving force in the FO process is provided by a different in osmotic pressure (concentration) across the membrane between the draw and poisonous metals solution sides. Experimental work was divided into three parts. The first part includes operating the forward osmosis process using T
... Show MoreThis research is marked by " lighting and processors formalism for spaces of shops selling mobile phones ," aims to " reveal about the relationship between lighting treatments formal designs spaces own internal selling mobile phone in addition to the recognition criteria Altsamama to lighting techniques and processes formality spaces shops competent to sell mobile phone " and lies the importance of this research in the " active role of the lighting in the building processors formalities and processes to prepare designs and show the final form integrated functionally and aesthetically so as to be ready for implementation , taking into consideration the role expressionist in the recipient and to make these spaces more than meet the require
... Show MoreThe provision of openings in serviceable reinforced concrete beams may result in a substantial decline in the beam's capacity and integrity, indicating the necessity of opening strengthening. The present study investigates the experimental response of reinforced concrete T-beams with multiple web-strengthened openings disposed in shear span to static and impact loads. Fourteen RC T-beams were tested in two groups, each of seven beams. The first group was tested under static loading up to failure, while the second group was tested under repeated impact loading until the width of shear cracks reached 0.3 mm. The residual static strengths of the beams subjected to impact loading were then determined. The test variables considered were
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