Background: Human teeth considered to be an important etiological host factor in relation to dental caries through its morphology and composition. Elements may incorporate in tooth structure during pre and post-eruptive period changing the resistance for caries. The aims of this study were to determine the concentration of selected major (Calcium and phosphorus) and trace elements (Ferrous iron, nickel, chromium and aluminum) in permanent teeth and enamel among a group of adolescent girls in relation to severity of dental caries Material and Methods: The study group consisted of 25 girls with an age of 13-15 years old referred by Orthodontists for extractions of upper first premolars (two sides). Tooth and enamel samples were prepared for chemical analysis according to method described by Lappalainen and Knuttila (1979). Dental caries was diagnosed by both clinical and radiographical examinations following the criteria of D1-4MFS index described by Muhlemann (1976). All data were analyzed using SPSS version 19. Results: The concentration of major elements in teeth and enamel (measured in % of dry weight) showed that Ca ions were higher than P ions. On the other hand the concentration of trace elements in teeth and enamel samples (measured in ppm) showed that Al ions was the highest followed by Ferrous Fe then Ni ions, while Cr ions were the least in concentration. All elements showed statistically highly significant difference in concentration between teeth and enamel samples. Ca/P ratio was higher in enamel than tooth, but the difference was statistically not significant. Major elements (calcium and phosphorus) in tooth and enamel samples recorded negative correlations with DMFS. Trace elements except chromium ions recorded positive correlations with DMFS. They were not significant except for nickel ions in tooth and aluminum ions in enamel. Conclusions: The presence of these elements in both teeth and enamel samples indicated that these elements present in our environment; as foods, water, and air so they incorporate through out the tooth layers during the pre-eruptive period of tooth development, and incorporate the outer enamel surface during the demineralization and remineralization processes that occurs in the post-eruptive periods. Ca and p ions play an important role in mineralization of tooth and enamel. Cr ions may play a role in improving mineralization and crystallity of teeth, while Fe, Ni and Al may act as cariogenic elements.
The effect of ethanol and methanol solvent, and their mixture has been studied on the absorption and fluorescence spectra of laser dye Rhodamine B at concentration of (10-4) Molar at room temperature. The molar absorption coefficient has been determined for mixture which was (3.223) at wave number (18181.8 cm-1), Also the Quantum Efficiency of the two solvents (ethanol and methanol) and their mixture have been calculated ,which was for mixture spectrum (38.94%) and it was larger comparing with other and solvents. The characteristics of spectrum has been determined by calculating (??) of absorption spectrum for the solvents and its mixture at maximum wave number ( ) cm-1 depending on solvent polarity and the transitions between molecular ene
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Arabic language , like any other living languages grow and evolve ; social phenomenon
it is subject to the law of life ; therefore resemble organism also touted as the most eloquent
language and the ability to meet the needs of people in every time and place.
The contemplation of the verses of the Koran reveals a lot of means of expression
leading to the grammatical meaning of the social.
I have tried in this research that investigated the social meanings through the phenomena
of deletion and delivery delays and capture semantic landing through the meanings that lead
to psychological persuasion to comply with the orders after the rights of the divine in which
social directives.
It remains the greatest mystery o
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A simple reverse-phase high performance liquid chromatographic method for the simultaneous analysis (separation and quantification) of furosemide (FURO), carbamazepine (CARB), diazepam (DIAZ) and carvedilol (CARV) has been developed and validated. The method was carried out on a NUCLEODUR® 100-5 C18ec column (250 x 4.6 mm, i. d.5μm), with a mobile phase comprising of acetonitrile: deionized water (50: 50 v/v, pH adjusted to 3.6 ±0.05 with acetic acid) at a flow rate 1.5 mL.min-1 and the quantification was achieved at 226 nm. The retention times of FURO, CARB, DIAZ and CARV were found to be 1.90 min, 2.79 min, 5.39 min and 9.56 min respectively. The method was validated in terms of linearity, accuracy, precision, limit of detection and li
... Show MoreTwo field experiments were conducted at two different texture sites. The first site of the fields of AlMed-hateya Agriculture Division / Babil Governorate. The second site of the fields of Al-Nouriah Research Station / Ministry of Agriculture, the factors of the study in the two sites included several factors. The first factor includes two irrigation systems: sprinkler irrigation and surface irrigation. The second factor is the method of cultivation which includes the method of cultivation with basin and furrowing. The third factor is the type of the cultivated crop which includes a local variety (Fajr 3) and a hybrid variety (Drakma). The actual water consumption for the sprinkler irrigation system reached (587.13 and 637.62) mm season-1 f
... Show MoreThe research deals with an important issue that many people are working on, namely the sanctification of the texts on which the timings of the time and the different conditions of the place took place. Do not live up to the ranks of perfection and perfection, and every effort has explanations according to the mind machine, which is not protected by infallibility from error. The great downfall is to put these intellectual efforts in the Bible without separating them from the Word of God. The situation and the place on the adherents of a religion and mixed with the trick of the average individual only to be subject to the words of the teachers of Sharia and docility.