Background: Calcium hydroxide and calcium-silicate materials used as direct pulp capping materials. The aims of this in vitro study is to compare among these materials in, the calcium ion release and pH change in soaking water after immersion of materials’ specimens in deionized water. Also Solubility and water sorption of materials’ specimens measured after soaking time. Calcium-silicate materials used were Biodentine, TheraCal and MTA Plus. Materials and methods: Four materials used in this study; Urbical lining (as control group), Biodentine, TheraCal and MTA Plus. Ten discs fabricated from each tested material, by using plastic moulds of 9 mm diameter and 1 mm thickness. Each specimen was immersed in 10 ml of deionized water and stored at 37ºC using incubator for 3 hr, 24hr, 14 days and 30 days as a sequence. The amount of calcium ion (Ca+2) released in soaking water was measured in each tube using atomic absorption spectrophotometer. Also pH analysis for soaking water measured by using pH meter. For solubility and water sorption measurement, the specimen (n=10) weighed with precision weighing scale before immersion in deionzed water to determine the initial Weight (W1) and immediately after weighing immersed in 10 mL of deionized water at 37 °C for 1 week using an incubator, then removed and weighing again (W2). The samples blotted dry using filter paper and dehydrated in an oven at 37 °C for 24 hr. and weighed again (W3). Then percentage of solubility and water sorption were determined. Data obtained were analyzed using one-way ANOVA and Tukey tests at 0.05 significant levels. Results: Statistical analysis showed highly significant differences (P<0. 05) among tested materials and in all tests (Ca+2 release, pH change, solubility and water sorption). Biodentine showed higher calcium ion released at four soaking time (3 hr, 24hr, 14 days and 30 days), with non significant difference with TheraCal and highly significant difference with MTA Plus and control group at 24 hr. immersion time; While MTA Plus showed non significant difference with control group at 24 hr. Less amount of calcium released was in control group. All tested materials induced alkalization of the soaking water that decreased with time. Means of solubility and water sorption showed that MTA Plus and biodentine had higher solubility in comparison with control group, while TheraCal showed less solubility than control group. The results of water sorption showed that less sorption percentage occurred in control group in comparison with other groups. Conclusion: calcium-silicate materials released more Ca+2 with time than calcium hydroxide. TheraCal showed less solubility and higher water sorption in comparison with control group. Biodentine and MTA Plus showed higher solubility and water sorption in comparison with TheraCal and control group.
In this research، a comparison has been made between the robust estimators of (M) for the Cubic Smoothing Splines technique، to avoid the problem of abnormality in data or contamination of error، and the traditional estimation method of Cubic Smoothing Splines technique by using two criteria of differentiation which are (MADE، WASE) for different sample sizes and disparity levels to estimate the chronologically different coefficients functions for the balanced longitudinal data which are characterized by observations obtained through (n) from the independent subjects، each one of them is measured repeatedly by group of specific time points (m)،since the frequent measurements within the subjects are almost connected an
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The problem of missing data represents a major obstacle before researchers in the process of data analysis in different fields since , this problem is a recurrent one in all fields of study including social , medical , astronomical and clinical experiments .
The presence of such a problem within the data to be studied may influence negatively on the analysis and it may lead to misleading conclusions , together with the fact that these conclusions that result from a great bias caused by that problem in spite of the efficiency of wavelet methods but they are also affected by the missing of data , in addition to the impact of the problem of miss of accuracy estimation
... Show MoreWeibull distribution is considered as one of the most widely distribution applied in real life, Its similar to normal distribution in the way of applications, it's also considered as one of the distributions that can applied in many fields such as industrial engineering to represent replaced and manufacturing time ,weather forecasting, and other scientific uses in reliability studies and survival function in medical and communication engineering fields.
In this paper, The scale parameter has been estimated for weibull distribution using Bayesian method based on Jeffery prior information as a first method , then enhanced by improving Jeffery prior information and then used as a se
... Show Moren this paper, we formulate three mathematical models using spline functions, such as linear, quadratic and cubic functions to approximate the mathematical model for incoming water to some dams. We will implement this model on dams of both rivers; dams on the Tigris are Mosul and Amara while dams on the Euphrates are Hadetha and Al-Hindya.
PVC/Kaolinite composites were prepared by the melt intercalation method. Mechanical properties, thermal properties, flammability and water absorption percentage of prepared samples were tested. Mechanical characteristic such as tensile strength, elongation at break; hardness and impact strength (charpy type) were measured for all samples. It was found that the tensile strength and elongation at break of PVC composites decreased with increasing kaolinite loading. Also, the hardness of the composites increases with increase in filler content .The impact strength of the composites at the beginning increases at lower kaolinite loadings is due to the lack of kaolin adhesion to the matrix. However, at higher kaolin loadings. This severe agglom
... Show MoreThis research was aimed to study the exposure of Razzazah Lake to major hydrological changes in recent years as a result of natural climatic changes and drought, high evaporation in lake due to stop discharge from Habbaniyah Lake by Al- majera channel. During 2019, we collected surface water samples at three locations, and three samples from groundwater, in addition one samples from each location Imam Ali Drop and Sewage water of Karbala. The Results show that the heavy isotopes in lake and groundwater well are enriched during the warm period, and depleted during the cold period. Chemically, The dominant cations and anions in Al-Razzaza lake water are mainly of in Order Ca > Na > Mg and Cl>SO4 and the water
... Show MoreOne of the important units in Sharq Dijla Water Treatment Plant (WTP) first and second extensions are the alum solution preparation and dosing unit. The existing operation of this unit accomplished manually starting from unloading the powder alum in the preparation basin and ending by controlling the alum dosage addition through the dosing pumps to the flash mix chambers. Because of the modern trend of monitoring and control the automatic operation of WTPs due to the great benefits that could be gain from optimum equipment operation, reducing the operating costs and human errors. This study deals with how to transform the conventional operation to an automatic monitoring and controlling system depending on a Programmable
... Show MoreTwo years field experiment was carried out at Agricultural Fields, College of Agriculture, Baghdad University, Al-Jadriya during 2014-2015 and 2015-2016 to determine the effect of salinity of irrigation water on growth and grain yield of three oat cultivars. The experiments were laid out according to randomized complete blocks design having split plot arrangements with two factors; first factor included three oat cultivars (Shifaa, Hamel and Pimula) while the second factor included three levels of salinity of irrigation water (3, 6 and 9 dS.m-1 ) in addition to the control (river water with salinity level of 1.164 dS.m-1 ) with three replicates. Results revealed a significant effect of salinity of irrigation water on all studied traits. Mea
... Show MoreA field experiment was conducted in Yusufiya sub-district - Mahmudiya township/Baghdad governorate in silty loam texture soil during the spring season of 2020. The experiment included three treatments with three replicates, as the Randomized Complete Block Design (RCBD) was used according to the arrangement of the split design block. The treatments are in the irrigation system, which included surface drip irrigation (T1) and sprinkler irrigation (T2). Secondly, the Irrigation levels including the irrigation using 0.70 Pan Evaporation Fraction PEF (I1), irrigation using 1.00 PEF (I2), and irrigation using 1.30 PEF (I3). Coupled with, Pota
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