Background: The aim of this study was to evaluate and compare the apical microleakage around retrograde cavities prepared with ultrasonic technique and filled with (Biodentine™) Materials and methods: 40 extracted single rooted human permanent maxillary teeth with mature apices were selected. The roots were prepared chemo-mechanically using k-files with crown-down technique and then obturated with lateral condensation gutta-percha technique. Teeth were divided into four main groups according to the cavity preparation method either manual or ultrasonic technique: Group A (n=10): A class I retrograde cavity at root end was prepared with traditional handpeice equipped and placement of Biodentine with manual condensation. Group B (n=10): A class I retrograde cavity at root end was prepared with Piezoelectric ultrasonic device equipped with ultrasonic tip with only manual compaction of the material. Group C (n=10): traditional handpeice and placement of Biodentine using both manual compaction and 5 second ultrasonic activation. Group D (n=10): Piezoelectric ultrasonic device and placement of Biodentine with both manual compaction and 5 second ultrasonic compaction. The teeth were immersed in 1% aqueous Methylene blue dye for 72 hr. Then they were sectioned longitudinally with a diamond disc and the depth of dye penetration was examined under high magnification 20X. Results: Statistical analysis showed a highly significant difference in microleakage among the tested groups in which Piezoelectric technique has proved superiority in retrograde cavity preparation and compaction of Biodentin when dye penetration scores were compared. So microleakage was highest with cavities prepared with handpeice and manual application of retrograde material group A (2.73±0.39) followed by microprepared cavities group C (1.86±0.16), and it was lowest with ultrasonically-prepared cavities group B (1.09±0.28) and group D (0.26±0.19). Conclusion: ultrasonic preparation produced significantly less microleakage than conventional method. Also less microleakage was observed with ultrasonic compaction of Biodentin when compared with conventional method of compaction.
A mixture model is used to model data that come from more than one component. In recent years, it became an effective tool in drawing inferences about the complex data that we might come across in real life. Moreover, it can represent a tremendous confirmatory tool in classification observations based on similarities amongst them. In this paper, several mixture regression-based methods were conducted under the assumption that the data come from a finite number of components. A comparison of these methods has been made according to their results in estimating component parameters. Also, observation membership has been inferred and assessed for these methods. The results showed that the flexible mixture model outperformed the
... Show MoreObjective(s): To determine the impact of Chemotherapy upon the quality of life for patients with chronic myeloid
leukemia in Baghdad city.
Methodology: A descriptive study design was carried out The study was initiated from 30 January 2011 to October
2011.A purposive (non–probability) sample consisted of (130) patients with a chronic myeloid leukemia ,Who
attended to Baghdad Teaching Hospital and National Center for Research and Treatment of Hematology. The
sample criteria was the patients who were 18 years old and above, excluding the patients who suffered from
psychological problems and other chronic illnesses .A questionnaire was adopted and developed from European
Organization Research and treatment of Can
This work presents experimental research using draped prestressed steel strands to improve the load-carrying capacity of prestressed concrete non-prismatic beams with multiple openings of various designs. The short-term deflection of non-prismatic prestressed concrete beams (NPCBs) flexural members under static loading were used to evaluate this improvement. Six simply supported (NPCBs) beams, five beams with openings, and one solid specimen used as a reference beam were all tested as part of the experiment. All of the beams were subjected to a monotonic midpoint load test. The configuration of the opening (quadrilateral or circular), as well as the depth of the chords, were the varia
The effects of the permeation cement grout with fly ash on the sandy soil skeleton were studied in the present work in two phase; first phase the shear strength parameters, and the second phase effect of these grouted materials on volume grouted zone by injection (51) cm³ of slurry in sandy soil placed in steel cylinder model with dimension 15 cm in diameter and 30 cm in height. The soil sample was obtained from Karbala city and it is classified as poorly graded sand (SP) according to USCS. The soil samples were improved by cement grout with three percentages weight of water cement ratio (w:c); (0.1w:0.9c, 0.8w:0.2c, and 0.7w:0.3c), while the soil samples were dehydrated for one day
... Show MoreThis study deals with the serviceability of reinforced concrete solid and perforated rafters with openings of different shapes and sizes based on an experimental study that includes 12 post-fire non-prismatic reinforced concrete beams (solid and perforated). Three groups were formed based on heating temperature (room temperature, 400 °C, and 700 °C), each group consisting of four rafters (solid, rafters with 6 and 8 trapezoidal openings, and rafter with eight circular openings) under static loading. A developed unified calculation technique for deflection and crack widths under static loading at the service stage has been provided, which comprises non-prismatic beams with or without opening exposed to flexure concentra
... Show MoreThe current research aims to identify the most important green productivity tools GPT and the possibility of applied in industrial companies in general and the companies operating in the province of Nineveh, in particular, as well as the study of some personality characteristics and functional, which is believed to be an impact on the application of these tools in industrial companies. Accordingly, the research community of managers in the company of medicines and medical supplies ready-made clothes _ operating in the province of Nineveh, who are (80) while the manager was subjected to research procedures (49) Director representing (61.25%)
... Show MoreMicrobial activity of Ellagic acid when mixed with some types of candy toward Streptococcus mutans microorganism was studied. The main purpose of carrying out this study is to produce a new type of candy that contains Ellagic acid in addition to xylitol instead of sucrose to prevent dental caries. The results show that the inhibitory action of Ellagic acid was more effective when mixed with this type of candy for the purpose of reducing Streptococcus mutans microorganisms, while sensory evaluation was applied in this study to 20 volunteers to that candy sample evaluated which contain (5 mg/ml) Ellagic acid with 100g xylitol to determine consumers acceptability of this sample of candy. The results were expressed as mean value, slandered d
... Show MoreThe study aims to reveal the degree of application of the alternative evaluation strategy in social studies in public education in the Kingdom of Saudi Arabia. It also aims to identify the opinions of experts on how to implement this. The study adopted the mixed methodology, which represented in the descriptive-analytical method, and qualitative methods through the grounded theory. The study used two tools namely: a questionnaire for assessments of social studies teachers and semi-structured interview questions. The results of the study showed a medium degree of appreciation for the application of alternative evaluation strategies by social studies teachers in general education with an average of (2.28). The results also showed that ther
... Show MoreThe objective of investigating some biochemical parameters like urea, creatinine, Hb and other parameters as CRP and leptin in the serum of ESRD patients on hemodialysis pre-dialysis. Method: Sample of 250 cases which consists of the patient with ESRD, their mean ages were 52.66 ± 12.55 years with ranged from 18-83. Moreover, under hemodialysis treatment not less than three months. Apparently, 20 healthy subjects were selected as (control) for comparison. Results: The results showed that there was a significant increase (p<0.01) in the serum urea, creatinine, CRP, and leptin. While, revealed significant (p< 0.05) decrease in the levels of uric acid, serum glucose, albumin, inorganic phosphorus, potassium, Hb and platelet in patien
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