Background: The bond strength of the root canal sealers to dentin is very important property for maintaining the integrity and the seal of root canal filling. The aim of this study was to evaluate and compare the push-out bond strength of root filled with total fill Bioceramic, AH Plus and Gutta-flow®2 sealers using GuttaFusion®obturation system versus single cone obturation technique. Materials and method: sixty of mandibular premolars teeth with straight roots were used in this study, these roots were instrumented using Reciproc system, instrumentation were done with copious irrigation of 3 mL 5.25% sodium hypochlorite solution (NaOCl) during all the steps of preparation, and smear layer will be removed with 1 ml of 17% EDTA kept in the canal for 1 min, roots were randomly divided into two groups according to the obturation technique (thirty teeth for each group): Group I: Single Reciproc Gutta percha cone obturation technique, Group II: Gutta fusion obturation technique, then each group divided into three subgroup according to the type of sealer, AH subgroup: AH Plus sealer, BC subgroup: bioceramic sealer and GF subgroup: Gutta flow 2 sealer. The roots then stored in moist environment at 37°C for one week, the roots were embedded in clear acrylic resin and each root sectioned into three levels apical, middle and cervical. The bond strength was measured using computerized universal testing machine each section fixed in the machine so that the load applied from apical to cervical direction at 0.5mm/min. speed and the computer show the higher bond force before dislodgment of the filling material. These forces were divided by the surface area to obtain the bond strength in MPa. Results: Statistical analysis was performed and the result showed a highly significant differences between the three types of sealers when the same obturation technique were used, also there is highly significant differences between two groups with two different obturation technique. Conclusion: This study showed that the push out bond strength of AH plus sealer was higher than bioceramic sealer and Gutta flow 2 sealer respectively when the same obturation technique was used. The push out bond strength was affected by the obturation technique and Gutta fusion obturation technique showed higher bond strength than single cone obturation technique when the same type of sealer was used.
Experts of Psychology and education emphasized that childhood is one of the most important stages in the formation of human personality, and the most influential in his public life, especially the stage in which he lives within his family, which must provide him with the requirements of healthy growth of physical, emotional, moral and social. Emotional-social connection of the child to his family, is especially important in determining the characteristics of his social character, in accordance with the norms and values prevailing in society. This requires the child to be cared for and cared for, and to deal with him in a healthy social manner. So as to achieve positive growth and harmony in the process of social control in internal
... Show MoreThe aim of the present work is to define a new class of closed soft sets in soft closure spaces, namely, generalized closed soft sets (
At the end of 2019, a new form of Coronavirus (later dubbed COVID-19) emerged in China and quickly spread to other regions of the globe. Despite the virus’s unique and unknown characteristics, it is a widely distributed infectious illness. Finding the geographical distribution of the virus transmission is therefore critical for epidemiologists and governments in order to respond to the illness epidemic rapidly and effectively. Understanding the dynamics of COVID-19’s spatial distribution can help to understand the pandemic’s scope and effects, as well as decision-making, planning, and community action aimed at preventing transmission. The main focus of this study is to investigate the geographic patterns of COVID-19 disseminat
... Show MoreIn this paper we generalize some of the results due to Bell and Mason on a near-ring N admitting a derivation D , and we will show that the body of evidence on prime near-rings with derivations have the behavior of the ring. Our purpose in this work is to explore further this ring like behavior. Also, we show that under appropriate additional hypothesis a near-ring must be a commutative ring.
Document clustering is the process of organizing a particular electronic corpus of documents into subgroups of similar text features. Formerly, a number of conventional algorithms had been applied to perform document clustering. There are current endeavors to enhance clustering performance by employing evolutionary algorithms. Thus, such endeavors became an emerging topic gaining more attention in recent years. The aim of this paper is to present an up-to-date and self-contained review fully devoted to document clustering via evolutionary algorithms. It firstly provides a comprehensive inspection to the document clustering model revealing its various components with its related concepts. Then it shows and analyzes the principle research wor
... Show MoreBackground: Multiple sclerosis (MS) is an inflammatory disease of the central nervous system, in which the myelin sheaths got injured. The prevalence of MS is on grow, as well as, it affects the young ages. Females are most common to have MS compared to males. Oxidative stress is the situation of imbalance between oxidants (free radicals and reactive oxygen species (ROS)) and antioxidants in a living system, in which either the oxidants are elevated or antioxidants are reduced, or sometimes both. ROS and oxidative stress have been implicated in the progression of many degenerative diseases, which is important in cracking the unrevealed mysteries of MS. In this review article, some of the proposed mechanisms that link oxidative stres
... Show MoreThe principal forms of radiation dosage for humans from spontaneous radiation material are being recognized as radon and its progenitors in the interior environment. Radiation-related health risks are caused by radon in water supply, which can be inhaled or ingested. Materials and Methods: The solid-state CR-39 nuclear trace detectors method was using in this research for measuring accumulation of radioactivity in water supply in different locations of Iraq's southwest corner of Baghdad. In Baghdad district, 42 samples were selected from 14 regions (3 samples out of each region) and put in dosimeters for 50 days. Results: The mean radon concentration was 49.75 Bq/m3, that is lower than the internationally recognized limit of 1100 Bq /m3. Th
... Show MoreThe present study aimed to shed light on the urine HSP70 concentration of patients with urinary bladder carcinoma UBC and control subjects as new urinary biomarker. The second aim was to associate this protein concentration with UBC stage and grade in patients with UBC. A direct ELISA was used to quantify urine HSP concentrations in 58 patients with urinary bladder carcinoma UBC with different grades (G) and stages (T) all malignant of them was transitional cell carcinoma (TCC) type , 15 from patients with urinary Bladder disorders other than cancer UBD and 15 healthy subjects(control) . Urine concentrations of HSP70 were elevated in patients with UBC compared to those without UBC (healthy and UBD, P< 0.5). There was a high signifi
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