Background: evaluate the effects of three different intracoronal bleaching agents on the shear bond strengths (SBS) and failure site of stainless steel and monocrystalline (sapphire) orthodontic brackets bonded to endodontically treated teeth using light cured orthodontic adhesive in vitro. Materials and methods: Eighty extracted sound human upper first premolars were selected, endondontically treated and randomly divided equally (according to the type of the brackets used) into two main groups (n = 40 per group). Each main group were subdivided (according to the bleaching agent used) into four subgroups 10 teeth each; as following : control (un bleached) group, hydrogen peroxide group (Hp) 35%, carbamide peroxide group (CP) 37% group and sodium perborate (SP) group . The bleaching process was applied three times (4 days intervals) sequentially and the bleached teeth were stored in artificial saliva four weeks before bonding. Orthodontic brackets were bonded with a light cure composite resin and cured with LED light. After passing 24 hours of bonding procedure, the brackets were debonded by a Tinius-Olsen universal testing machine, to measure the shear bond strength. After debonding, each bracket base and the corresponding tooth surface were examined using a stereomicroscope and their Adhesive Remnant Index (ARI) was recorded. Results: The ANOVA test showed that the SBS of stainless brackets was significantly reduced by intracorornal bleaching agents. Furthermore, LSD showed no significant difference in SBS between the three types of bleaching agents used in stainless steel group. Whilst for sapphire group, the results The ANOVA test showed no significant difference in SBS between the bleached groups and the control group. Chi-square comparison no significant difference in failure site between bleached and control groups in both brackets types used. Conclusion: The effect of intracoronal bleaching on SBS was reduced SBS of stainless steel and not for sapphire. However, the intracoronal bleaching had no effect on the failure site of orthodontic brackets used.
Tenofovir disoproxil fumarate, a nucleotide reverse transcriptase inhibitor utilized for the treatment of hepatitis B virus and human immunodeficiency virus infections; and is now one of the most widely used antiretroviral drug. However, tenofovir disoproxil fumarate can induce nephrotoxicity, which may be attributed to the interaction between such drug and the organic anion transporters (hOAT1, and OAT3) with consequent changes in levels of some parameters that may have a role in nephrotoxicity. Thiazide diuretics have high to intermediate potency of inhibition of OAT1s and OAT3; thus, it may possess nephroprotective effects. This study was designed to investigate whether hydrochlorthiazide has nephroprotective effects on tenofovir diso
... Show More
(2)
(1)
Both methotrexate and vitamin D3 are used in combination for the treatment of various diseases. The aim of this study is to highlight the effect of vitamin D3 on methotrexate-induced jejunum damage using biochemical and histopathological studies. Seven groups of both sexes of rats were selected and treated as follows: (Group I and Group II) : control 1,control 2 (I.P normal saline) daily for 14 and 21 days respectively ; (Group III and Group IV) :vitamin D3 groups (500 IU/rat/day) orally for 14 and 21 days, respectively;(Group V): once daily dose of methotrexate 20mg/kg, I.P injected for 4 days;(Group VI):vitamin D3 (500 IU/rat/day) once daily for 14 days and methotrexate (20 mg/kg I.P) injected only at day 10;.(Group
... Show More
(21)
(13)
This investigation showed (31) species belonging to (15) genera under (five) families and two orders. The leafminers Dipter families (Agromozidae, Anthomyiidae, Drosophilidae), Agromyzid flies is the highest level of investigated many host plants, but other families have lowest host plants. The synonyms of species were provided from GBIF scarlet's. The date and localities of sampling collection were recorded.
(2)
(4)
(1)
The Gender study is consider one of the concepts which the Postmodernism reached
after the end of Modernism, where the first one has limited the criticism study choices before
the second after closed many doors of subjects which was enriched by researches.
It is pretty clear that the root of this concept belongs to the Linguistics which provided
the Criticism with a countable reasons of it is growth.
The attention in the study of gender in Feminine Literature and Criticism increased in
Arabic studies since the early years of twenty one century, so this research is presented to be
an introduction to this subject which could pave the way to more studies.
In addition to the Gender studies this research deals with ano
Human cerebral cortex is the outer folded neuronal layer and represents major part of the cerebrum with enormous functions. It is a laminar structure, easily visualized grossly. Previous studies showed that the Superior Temporal gyrus is one of the thickest cerebral cortex regions, reaching (about 4 mm). The Electron microscope study was made on 6 samples taken to measure the neuronal soma dimension of the large pyramidal cells present in the internal pyramidal cortical layer V in different age groups and gender. Aging process was obvious on the large pyramidal cells of the cerebral cortex, in which their neuronal soma dimensions showed shrinkage with age progression. But statistically there was no differences in the values between males an
... Show MoreThis Study aimed To know The relation between Types of blood and health problems which human Suffered from , and the effect of food intake on health.
Samples of study contained 269 person aged between 30 – 70 years which choiced randomly for sex , we are take all in formation about samples of study by form paper contian sex , age, type of blood , weight (kg) , height (cm) , smoking or.not , sporting or not, problems in digestive tract , sensitivity for foods , heart problems , ratio of cholesterol in blood , Sinusitis , Asthma , diabetic meliuts , arritable bowel syndrome , diaherra , problems in kidney and urination , hypertension , anemia , alternation in liver function , arthritis with form record in daily food intake and its ade
An environmental study conducted on diatoms in Al Yusifiya river beyond its branching from Euphrates river. Four sites were selected along the river for the period from march 2013 to September 2013. The present study involved the measurement of physicochemical parameters, also the qualitative and quantities of diatoms. The studied parameters values ranged as follows: 19-44Cº and 16-30 Cº for air and water temperature respectively, 6.9-8.7, 595-1248 µS/cm, 6.4-8.0 mg/l for pH, electric conductivity and dissolved oxygen respectively. A total of 74 taxa were recorded for diatoms, where the pinnate diatom was the predominant and recorded 64 taxa while 10 taxa for centric diatoms. The total number of diatoms was 1197.55*104 cell /l. The tota
... Show More