Objective: This study evaluated the effect of immediate dentin sealing on the marginal adaptation of lithium disilicate overlays with three different types of resin-luting agents: preheated composite, dual-cure adhesive resin, and flowable composite. Materials and Methods: Forty-eight maxillary first premolars of similar size were prepared with a butt joint preparation design. The teeth were separated into two primary groups, each with twenty-four teeth: Group DDS: Delay dentin sealing (non-IDS) teeth were not treated. Group IDS: dentin sealing was applied immediately after teeth preparation. Each group was subsequently separated into three separate subgroups. Subgroups (DDS+Phc, IDS+Phc): cemented with preheated composite (Enamel plus HRi, Micerium, Italy), Subgroups (DDS+Dcrs, IDS+Dcrs): cemented with dual-cured resin cement (RelyX Ultimate, 3M ESPE, Germany) and Subgroups (DDS+Fc, IDS+Fc): Cemented with flowable composite (Filtek supreme flowable, 3M ESPE, USA). Using a digital microscope with a magnification of 230x, the marginal gap was measured before and after cementation at four different locations from each surface of the tooth, and the mean of measurements was calculated and analyzed statistically using the independent t-test, one-way ANOVA test, Bonferroni correction at a significance level of 0.05. Results: The samples that were immediately sealed with dentin bonding agent showed lower marginal gaps than delayed dentin sealing, both pre-and post-cementation for all subgroups, with a statistically significant difference (p < 0.01). The marginal gap was significantly lower in the IDS+Fc (48.888 ± 5.5 micro m) followed by the IDS+Dcrs group (53.612 ±5.8 micro m) and IDS+Phc (79.19 9±6.9 micro m) respectively, while the largest marginal gaps were observed in the DDS+Phc group (86.505 ± 5.4 micro m). Conclusion: Generally, the teeth with IDS showed better marginal adaptation than teeth without IDS. The marginal gap was smaller with flowable composite and dual-cure resin cement than with preheated composite.
Field experiment was conducted during 2007 in the experimental field of crop science Department/ Collage of Agriculture/ University of Baghdad, in order to identify the mechanism of compensation of cotton plant of Lashata Variety, with different levels of fruiting form removal in various time intervals and the effect of this factor on yield component. We use complete randomized block design with three replications. To compare the treatments: (control), 50% bud removal for one, two and three successive weeks, and 100% bud removal for one, two and three successive weeks, 50% flower removal for one, two and three successive weeks and 100% flower removal for one, two and three successive weeks, 50% boll removal for one, two and three successive
... Show MoreThis study was conducted to the college of education ( Ibn Al- Haitham ) – University of Baghdad ( 2001 – 2002 ) to evaluate the barley ( Hordeum vulgare L. ) response to effect of salinity and salinity with calcium in the growth medium . Seed germination was carried out in petridishs by using the nutrient solution of Arnon and Hoagland containing different concentrations of NaCl ( 0,50,100 and 150 mM ) and these concentrations with 5mM calcium sulfate . Plant growth was continued in hydroponic culture in green house for 4 weeks . Results showed that salinity caused a decrease in the percentage of germination, plant growth , pro
... Show MoreThis study aimed to determine the possibility of culturing genus Artemia in under laboratory conditions for locally culturing and producing. Different salinity concentrations were used, ranging from 5-40g/l . the results showed that the concentration 30g/l is the best for hatching. This concentration recorded hatching efficiency of 68800 nauplii/g cysts and hatching percentage of 45.86%, while the concentration 5g/l recorded less hatching efficiency and hatching percentage of 20266 nauplii/g and 13.5% respectively . Investigating the effect of salinity on individuals survival and growth using saline concentrations ranging from 30to 100g/l, revealed that the best percentage was 75.00% in the first week with 70g/l, whilst the best rates of
... Show MoreVacuum evaporation technique was used to prepare pure and doped ZnS:Pb thin films at10% atomic weight of Pb element onto glass substrates at room temperature for 200 nm thickness. Effect of doping on a.c electrical properties such as, a.c conductivity, real, and imaginary parts of dielectric constant within frequency range (10 KHz - 10 MHz) are measured. The frequency dependence of a.c conductivity is matched with correlated barrier hoping especially at higher frequency. Effect of doping on behavior of a.c mechanism within temperature range 298-473 K was studied.
Orthodontic tooth movement is characterized by tissue reactions, which consist of an inflammatory response in periodontal ligament and followed by bone remodeling in the periodontium depending on the forces applied. These processes trigger the secretion of various proteins and enzymes into the saliva. The purpose of this study was to evaluate the activity of the lactate dehydrogenase (LDH) in saliva during orthodontic tooth movement using different magnitude of continuous orthodontic forces. Thirty orthodontic patients (12 males and 18 females) with ages 17-23 years with class II division I malocclusion all requiring bilateral maxillary first premolar extractions. Those patients were randomly divided into 3 groups according to the magnitude
... Show MoreIn this study, Epoxy Resin plates was prepared by mixing epoxy(A) and hardner(B)with ratio(A:B) (3:1) with different thickness (0.3-0.96)cm. The effect of thickness on optical properties have been studied (absorption ,transmission ,reflectance) also the optical constant were found like (absorption coefficient, extenuation coefficient and refraction index) for all of the prepared plates. The results have shown that by increasing the thickness of plates., the absorption intensity increase in which at plates thickness (0.3-0.96)cm the absorption intensity were(1.54-1.43) respectively, and since absorption peak for epoxy occur in ultraviolet region and exactly at wavelength(368)nm and energy gap(Eg=3.05 eV) thus their good transmittance in the
... Show MoreBixSb2-xTe3 alloys with different ratios of Bi (x=0, 0.1, 0.3, 0.5, and 2) have been prepared, Thin films of these alloys were prepared using thermal evaporation method under vacuum of 10-5 Torr on glass substrates at room temperature with different deposition rate (0.16, 0.5, 0.83) nm/sec for thickness (100, 300, 500) respectively. The X–ray diffraction measurements for BixSb2-xTe3 bulk and thin films indicate the polycrystalline structure with a strong intensity of peak of plane (015) preferred orientation with additional peaks, (0015) and (1010 ) reflections planes, which is meaning that all films present a very good texture along the (015) plane axis at different intensities for each thin film for different thickness. AFM measureme
... Show MorePain is a sensory and emotional experience that is influenced by physiologic, sensory, affective, cognitive, socio-cultural and behavioral factors. Postoperative pain is the commonest reason for delayed discharge and unanticipated hospital admission after ambulatory surgery. Our Objective is to test the hypothesis that administration of 2 ml/kg/hr preoperative IV fluids may attenuates postoperative pain.The study was carried out in the Baghdad Teaching Hospital, Al-Yarmok Teaching Hospital and Al-Karama Teaching Hospital from 12 May till 17 June 2009. The total number of patients was 120 (35 males and 85 females) with their age ranged between 10-90 years. The patients were divided into two groups according to administration of preoperati
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