Background: Esthetic treatment is the options of patient seeking orthodontic treatment. Therefore this study was conducted to measure the concentration of Aluminum, Nickel, Chromium and Iron ions released from combination of monocrysralline brackets with different arch wires immersed in artificial saliva at different duration, to evaluate the corrosion point on different parts of the orthodontic appliances before and after immersion in artificial saliva, and to evaluate the corrosion potential of each group of the orthodontic appliances. Material and methods: Eighty orthodontic sets prepared. Each set represents half fixed orthodontic appliance, from the central incisor to the first molar, for the maxillary arch, each set consisted of molar band, five brackets, half arch wire and ligature elastic.These sets are divided into two groups: Group A: with monocrystalline brackets divided into five subgroups (each subgroup has ten sets), but differ in arch wires, as numbered stainless steel, nickel-titanium, thermally activated, coated stainless steel and coated nickel-titanium arch wires respectively. Group B: with stainless steel brackets divided into three subgroups (also each subgroup has ten sets), but differ in arch wires, as numberedstainless steel, nickel-titanium, and thermally activated arch wires respectively. Used optical microscope to check the corrosion points, and used potentiostat techniques to indicate corrosion rate and tendency. Results: The greatest concentration of Aluminum and nickel ions release during the 1st week in group A, then sharply decreased in the 2nd week. The release of chromium ion released increase with increase intervals, while iron ion released decrease with increase time. Both nickel and chromium ions increase with increase intervals in group B,while iron increase to the maximum at 3rd weeks, then began to degrease. Optical microscope displayed pitting, crevices, and intergranular corrosion. Potentiostat techniques indicated that increase corrosion when used stainless steel and coated nickel titanium than others arch wires with group A, while corrosion increase with nickel titanium than stainless steel arch wires with group B. Conclusions: Non-significant difference in the total nickel, chromium and iron release in group B. Aluminum and iron increase in A4 and A5, while nickel and chromium increase in A1 and A2.The total released amounts of metals ions in both groups were less than the amounts of daily intake.
Thanks allah and peace be upon our prophet muhammed and upon his family and his
followers……
Love means in holy quran what comes to people s mind nowadays and what it inspired its
signi ficence is related with sensual desire and it means adore and passion .by the waythe
word (ishiq) adore wasn’t mentioned in holy quran which means that both of their bases are
farfrom each oiter in m eaning.
The significance of love means virtue while adore means the excess and desire so adore is
dis praised . as al askari said (died 395h )between love and adore.adore is the strain of desire
to get the purpose from lovers if it was ahuman who intended to make love affairs.
Today both of love and adore changed in their meani
A revision of 47 references for the last ten years, from 2010 to 2020, concerning gizzard and intestinal helminthic parasites of some birds in Iraq, showed infections with trematodes, cestodes, nematodes and one acanthocephalan. Helminthic infections of birds were arranged in three tables according to bird order, in each table, bird orders arranged according to the number of infected bird species descending. Among the class Trematoda, the bird order with more infected members found each of Anseriformes and Charadriiformes found that 5 bird species infected with trematodes, followed by Gruiformes 2 bird species, then Passeriformes with 2 species and one bird species for each of Pelecaniformes and Phoenicopteriformes. In the class Cestoda, th
... Show More20 specimens of the quail bird belonging to the family Phasianidae were collected from different and random areas of Baghdad city (central Iraq) for the period between February-May 2017 were examined for blood parasite. Only one genus, the Plasmodium sp. was identified in 10 samples with 50% infection rate.
Osteoporosis (OP) is asymptomatic disease until the experience of falls or impacts that cause broken bones or fractures happened. Estrogen deficiency, abnormality in bone matrix components and interleukins expression can impact on bone homeostasis which gradually paved to osteoclastogenesis over activation leading to bone loss. A current case-control study was designed to explain the alteration in certain biochemicals, bone matrix components, immunological and molecular parameters that which accompanied with OP in the postmenopausal women. The period of study's investigation was from December 2022 to July 2023. All participants provided written informed consent, and the study was approved by Department of Biology, College of Science, U
... Show MoreThe aim of this study is to recognize the influence of model of active thinking in achievement ofeighth grade students andtheir visual thinking in science.The finds of this research show the superiority students of the experimental group who studied the science material by using the active thinking model on the students of the control group who studied by usual method, in the achievement test. Also the finds show that the students of the experimental group are more successful than students of control group in the test of visual thinking, so the two null hypotheses have been rejected. In light of the results of the research, numbers of recommendations were made.
This research aims to clarify and define the most important philosophical and rhetorical concepts to which many philosophical and rhetorical issues refer، since they have an effective role in the diversity and difference of intellectual schools، which are indispensable in proving major dogmatic issues، such as the concept of (existence، being، essence، and authenticity). Existence or Essence in contrast to the consideration of the other concept)، because it is one of the complex concepts and common words that carry different connotations among thinkers.
And from (the rule of judging something is a branch of its perception)، the researchers began to define these concepts، as evidence of the sincerity of perce
... Show MoreThe critical micelle concentration (CMC) of nonylphenolethoxylate (NPE) surfactant has been determined by measuring the surface tension as a function of the molar concentration of the surfactant in aqueous and binary mixture of water + methanol solutions at a temperature range from 20?C to 35?C. The interfacial parameters ?max, Amin, ?cmc and ?G?ads were calculated. The results indicate that the CMC increases as the temperature increases and that the addition of methanol the CMC decreases. The thermodynamic parameters such as standard Gibbs free energy (?G?), enthalpy (?H?), and entropy (?S?) of micellization were estimated using the change of CMC with temperature. The enthalpy – entropy compensation behavior of the surfactant was evaluat
... Show MoreBackground: Oral lichen planus (OLP) is a relatively common chronic inflammatory muco-cutaneous disease classified among the potentially malignant lesions of oral mucosa. The aim of this study is to investigate and compare the expression of p53 and PCNA proteins in oral lichen planus and epithelial dysplasia cases. Materials and methods:Formalin-fixed and paraffin- embedded blocks of 21 lichen planusand 21 oral dysplasia cases were referred to immunohistochemical (IHC) analysis for anti p53 and anti PCNA monoclonal antibodies. Results: The results showed that positive nuclear staining for p53 was found in 11/21 (52.4%) cases of lichen planus and 17/21 (80.9%) cases of dysplasia. Positivity for PCNA was observed in 18/21(85.7%) of oral li
... Show MoreBackground: Adenoid cystic carcinoma (ACC) constitutes about 4% of salivary epithelial tumors and is the second common malignant epithelial salivary gland tumor involving both the major and minor salivary glands. Aims of the study is to evaluate immunohistochemical expression of Ki67 and p53 proteins in ACC. Materials and Methods: immunohistochemical analyses of fifteen cases of formalin – fixed paraffin – embedded tissues blocks of ACC of salivary glands using ki67 and p53 antibodies. Results: ki67 was expressed in 6 of 15 ACC (40%) while p53 aberration was demonstrated in 11 of tumor (73.3%). There was a statistically significant difference between the expression of ki67 and p53 proteins in ACC cases (p value = 0.041). Pearson’s cor
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