Background: This study evaluated the influence of different fiber formulations incorporation in resin composite on cuspal deflection (CD) of endodontically-treated teeth with mesio-occluso-distal (MOD) cavities. Materials and Methods: Thirty-two freshly extracted maxillary premolar teeth received MOD cavity preparation followed by endodontic treatment using single cone obturation technique, and divided into: Group I: direct composite resin only using a centripetal technique, Group II: direct composite resin with short fiber-reinforced composite (everX Flow), Group III: direct composite resin with leno wave ultra-high molecular weight polyethylene (LWUHMWPE) fibers placed on the cavity floor, and Group IV: direct composite resin with LWUHMWPE fibers placed circumferentially around the cavity walls (wallpapering technique). The CD was measured using a novel digital evaluation method, whereby each tooth was scanned by a desktop scanner (Medit T710) at three different time intervals: before and after cavity preparation, and after restoration. The intercuspal distance (ICD) was measured digitally in μm at each interval using Medit compare metrology software, followed by measurement of the CD by subtracting the ICD after cavity preparation; and after restoration from the before preparation one to obtain the “after cavity preparation CD1” and “the after restoration CD2”, respectively. The data were analyzed using one-way ANOVA and Tukey HSD tests at a significance level of 0.05. Results: The highest CD was recorded in Group I with statistically significant differences with all other groups (P<0.05). No statistically significant differences were found between the other groups (Groups II, III, and IV) (P>0.05). Conclusions: There was an inward deflection of the cusps in all groups following cavity preparation and restoration as elicited by the negative CD1 and CD2 values. The incorporation of fibers, regardless of their type or orientation, resulted in a significant reduction in CD of endodontically treated premolar teeth as compared with those restored with resin composite alone.
ِabstract:In this research we prepared nanofibers by electrospinning from poly (Vinyl Alcohol) /TiO2. The spectrum of the solution (Emission) was studied and found to be at 772 nm, several process parameters were such as concentration of TiO2 , and the effect of distance from nozzle tip to the grounded collector (gap distance). The result of the lower concentration of, the smaller the diameter of nanofiber is. Increasing the gap distance will affect nanofibers diameter.
Two new simultaneous spectrophotometric methods for determination of Olanzapine and Ephedrine depend on third (D3) and fourth (D4) derivative of zero spectrum of two drugs were developed. The peak – to- base line, peak to peak and area under peak were found proportional with concentration of the drugs up to (4-24 µg/ml-1) at known experimental wavelengths. The results showed that the method was precise and accurate through RSD% (0.5026-4.0273),( 0.2399 6.9888) and R.E %(-2.3889-0.8333) ,) -2.9444-0.2273) while the LOD (0.0057- 0.8510 μg.ml-1), ( 0.0953-0.9844 μg.ml-1) and LOQ (0.0173- 2.5788μg.ml-1),( 0.5774-2.9829 μg.ml-1) were found for the two drugs respectively. The methods were applied i
... Show MoreBackground: Goiter is one of the most common conditions that affect people’s at different age groups with its effect on the metabolic status of the body through the hyper&/hypo functioning gland that may needs surgical resection. This prospective study had been conducted on 100 patient (85 females&15 males} at the specialized center for endocrinology and diabetes mellitus in Baghdad city, between Jan.2013-Oct.2014;Their ages were ranging between 11-75 years ; the median age is (40.5 years) .Objectives: define the clinic-pathological pattern of goiter in the center .Methods: This is a prospective study at the specialized center for endocrinology & diabetes in Baghdad at ALRissafa district; including 100 patients (84 f
In this work, the synergistic effect of chlorinated rubber (additive I),with zeolite 3A (additive II), zeolite 4A (additive III), and zeolite 5A (additive IV) in (1:1) weight percentage, on the flammability for unsaturated polyester resin was studied in the weight ratios for (3,7,10,13&15%) by preparing films of (130×130×3) mm in diameters. Three standard test methods used to measure were the flame retardation which are; ASTM: D-2863, ASTM: D- 635& ASTM: D-3014. Results obtained from these tests indicated that all of the additives were effective additive IV has the highest efficiency as a flame retardant.
The pharmacokinetics and bioequivalence of a newly developed extended-released (ER) tablet containing 400 mg pentoxifylline as a test product was compared with the reference brand product Trental® 400 mg ER tablet produced by Sanofi-Aventis. Two separate studies were conducted simultaneously. The first study was conducted under fasting condition, whereas, the second study was conducted under fed condition; using the same batches of the test and reference products in both studies. In each study, both products were administered to 32 healthy male adult volunteers applying a single-dose, two-treatment, two-period, two-sequence, randomized crossover design with one-week washout period between dosing. Twenty two blood samples we
... Show MoreThe current research aims to reveal the level of satisfaction of the mentors with the evaluation of their performance according to gender (male - female) and to formulate the predictive equation for the level of performance (dependent variable) from knowing the level of satisfaction with the evaluation (independent variable). (16 paragraphs) contains alternatives to the answer that measures the level of satisfaction (weak, medium, and high) (1,2,3), that is, with a hypothetical average of (32). It consisted of 100 educational counselors consisting of 45 males and 55 females, the results of the research concluded that the level of satisfaction with performance is below the mean when compared with the hypothetical average of the scale of s
... Show MoreOverlapped have been prepared from epoxy resin material added to carbon Nanotube and percentages weight (0.1, 0.05, 0.01) % Studied the mechanical properties of the composite (bending, tensile an d hardness) has been found that the Flexural and tensile modulus of the composites were higher than the pure epoxy resin this may be due to the high mechanical strength of carbon nano tube (CNT). The hardness of the epoxy carbon Nanotube composites increased and the reason is due to increased overlap and stacking between the additives and material basis, which reduces the movement of polymer molecules leading to increased resistance to scratching material and cutting, will become more resistance to plastic deformation.
This investigation presents an experimental and analytical study on the behavior of reinforced concrete deep beams before and after repair. The original beams were first loaded under two points load up to failure, then, repaired by epoxy resin and tested again. Three of the test beams contains shear reinforcement and the other two beams have no shear reinforcement. The main variable in these beams was the percentage of longitudinal steel reinforcement (0, 0.707, 1.061, and 1.414%). The main objective of this research is to investigate the possibility of restoring the full load carrying capacity of the reinforced concrete deep beam with and without shear reinforcement by using epoxy resin as the material of repair. All be
... Show MoreGenistein (GEN) is The major isoflavone found in soybeans, has a number of cardiovascular health benefits, Postmenopausal syndrome and osteoporosis. A direct flow injection analysis method for estimation of (GEN) in pure and supplements formulation . This system is based on diazotization coupling reactions between procaine penciline (PR) and genistein in basic medium, they formed yellow dyes have maximum absorption at 416 nm. Calibration curve were constructed over different GEN concentrations, linearity for GEN was 10-100 µg.mL-1 and detection limits of 1.51 ?g/mL. In the FIA technique, all analytical factors were analyzed and optimized. The established method was successfully used to determine GEN in the formulations of its supplement
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