RESUMO
Recent clinical results for Zirconia all-ceramic restorations have revealed that the fracture rate 6-15% of the Zirconia framework is so low and the core of Zirconia has high stability. However, chipping-off fractures of porcelain are the most common reason for failures of Zirconia in the fixed partial dentures
Objectives: The purpose of this study was to compare the shear bond strength [SBS] of porcelain in the porcelain fused to metal and all-ceramic crowns with Zirconia core
Materials and Methods: Two groups were selected: porcelain fused to metal [PFM] and porcelain fused to Zirconia [PFZ] [n = 30].In the PFM group, a wax model [10 × 10 × 10mm]was used to cast metal base [Ni_Cr alloy]. In the PFZ group, an acrylic cubic model [10 × 10 × 10mm] was made as Zirconia model for scanning.15 cubic Zirconia samples were milled by CAD-CAM. The procedure of porcelain veneering was conducted by the conventional layering technique up to 2 mm thickness [2.5 × 2.5 × 2 mm]. All specimens were stored in water for 48 hrs. Thermal cycling was conducted for 20000 cycles between 55[degree sign]C and 5[degree sign]C alternatively for 30s.All samples were mounted in acrylic resin and the SBS test was performed, using a universal testing machine. The analysis of data was performed at a significance level of 0.05 using Kolmogorov-Smirnov and Mann-Whitney U-test
Results: Mean of SBS in PFM and PFZ was 24.57 and 20.88, respectively. The results of Mann-Whitney test showed that there was no statistically significant difference between the two groups of porcelain fused to metal and Zirconia in item shear bond strength [p = 0.455]
Conclusions: There was no significant difference between the two groups of PFM and PFZ in the item SBS
RESUMO
Inulin is widely used in functional foods throughout the world for its health-promoting and technological properties. Burdock tuber can be a valuable source of inulin. It is cultivated widely in the northern and western parts of Iran. But scarce studies about its extraction exist. It has been increasingly used in functional foods due to its texture improvement, sugar and fat replacer characteristics and beneficial nutritional attributes, as prebiotic ingredient. Optimize conventional extraction of inulin, by using central composite design [CCD] and response surface methodology [RSM]. In this Research, a series of statistically designed studies such as central composite design and response surface methodology were performed to investigate the effect of each of the independent variables, solvent: solid ratio [5 - 15 v/w], temperature [40 - 90°C] and time [5 - 40 min] on yield of inulin extraction from burdock tubers. Response surface methodology was employed to optimize multiple variables to predict the best performance conditions with a minimum number of experiments. According to determination of inulin content of extraction liquid, firstly total carbohydrate was determined by the phenolsulphuric acid method, then reducing sugar was determined by the dinitrosalicylic acid method and finally the inulin content was measured with the difference between total carbohydrate and reducing sugars. Inulin extraction yield [%] was calculated using the following relationship = [inulin content x volume of extraction liquid/mass of Burdock tuber powder] x100. Based on canonical analysis, the optimal conditions for maximizing inulin extraction yield [12%] were at 66.14°C for 37.6 min and solvent: solid ratios of 14: 98 [v/w]. Using the response surface methodology, the optimum set of the independent variables was obtained graphically in order to obtain the desired levels of inulin extraction
Assuntos
ArctiumRESUMO
Animal studies reveal that conjugated linoleic acid [CLA] alters body composition, but few studies have examined the effects of CLA supplementation on body composition and leptin concentration in post menopausal women. In the present study, A randomized, double blind, placebo-controlled trial was performed to examine the changes in body composition and leptin concentration following 12 week supplementation of either 4 capsules of CLAG80 containing 3.2g CLA [50: 50 ratios of cis-9, trans-11 and trans-10, cis-12 isomers] or 4 placebo capsules [high oleic sunflower] in post-menopausal women. Seventy-six healthy post-menopausal women were randomized to receive placebo or 3.2g CLA for 12 weeks. Dual-Energy X-Ray Absorptiometry was used to measure body composition at baseline and after 12 weeks. Blood samples were collected after 10-12 hours fasting before and after intervention in order to determine leptin levels. Subjects completed 3 day dietary records during the trial, at week 0 [baseline], and at weeks 6 and 12. These dietary records were coded by the same dietitian, and analyzed using Food Processor II. Anthropometric measurements were done according to standard methods. Baseline data for time since menopausal age, BMI, fat mass, lean mass, waist circumference, physical activity and systolic and diastolic pressure were similar in both groups. Dietary CLA in the CLA and placebo groups were 104.5 +/- 43.2 mg and 99.5 +/- 38.2 mg respectively. Although lean body mass increased by 0.87 kg in the CLA group [p<0.00] after 12 weeks of intervention, leptin concentration did not change in either group. Conjugated Linoleic Acid supplementation improves loss of skeletal muscle in postmenopausal women