ABSTRACT
The aim of this study was compare the effects of fasting during Ramadan [as a dietary pattern] and regular aerobic exercise on HSP70, lipid profile and insulin resistance indexes in non-active obese men. In this study, 18 obese men, aged between 50-40 years, with a BMI over 30 kg/m[2] per square meter were randomly selected from among 70 volunteers responding to a public call. They were then divided into two, the fasting [N=9] and the fasting with exercise [N=9] groups. While the first group just fasted, the fasting and exercise group in addition to fasting performed 27 sessions of exercise at an intensity of 50-70% of their VO2max. Also, to study the desired changes in Ramadan, blood samples were taken at four different times points and finally, using repeated measures analysis of variance at the significance level of p<0.05, data was analyzed. Results showed that HSP70 levels in both groups increased during Ramadan. Also, HSP70 levels in both the fasting and the fasting with exercise groups increased, during the fourth week of Ramadan, the difference between the groups being significant [F=23.25; p=0.001]. Insulin resistance also decreased in both groups, a reduction that was significant in the fasting group [F=3.244; p=0.042]. Additionally, only in the fourth week of Ramadan and two weeks after that the lipid profile of the participants decreased and their HDL-C increased, changes all significant [p<0.05]. The research results show that the increased levels of HSP70 as a result of fasting perse, and fasting with exercise, may lead to decreased insulin resistance in obese men
ABSTRACT
With more polymerization rate there would be less time for the composite to flow and consequently sudden hardening occurs. This leads into composite detachment from cavity walls resulting in micro leakage between the restoration and tooth, and will decrees the bond strength. The aim of this study was to investigate the shear bond strengths of the enamel and dentin resin composite using Suggested Progressive program [SUP] and some other light exposure patterns. In this experimental in vitro study, the test groups were composed of 40 dentinal and 40 enamel samples prepared on facial surfaces of 80 human canine teeth. 2x2mm polyethylen cylandric molds were filled in bulk with Tetric Ceram composite and were placed on the prepared surfaces. Irradiation patterns for 4 groups of 10 dentinal and 10 enamel samples were as follows: Group 1, HIP [High Intensity Program]. Group 2, LOP [Low Intensity Program]. Group 3, PUL [Pulse Program] of Astralis 7 light curing unit exposure patterns, and Group 4, SUP [Suggested Progressive Program]. After curing and 24 hours incubation in 37°C, the samples were thermocycled under 500 cycles [5-55°C], and mounted with acrylic resin. Shear bond strengths of all samples were obtained using the Instron testing machine with 0.5 mm/min crosshead speed. For statistical analysis, one way and two way ANOYA and Duncan testes were used by SPSS software. There was no significant difference between the shear bond strengths of four light exposure patterns in dentinal and enamel groups [p < 0.001]. It was also revealed that various light exposure patterns had no significant effect on shear bond strength of composite to enamel and dentin [p = 0.388]. SUP light exposure pattern has the same capability of producing appropriate bond strength with the tooth structures as other light exposure patterns
Subject(s)
Composite Resins , Dental Enamel , Dental Leakage , Dentin , Light-Curing of Dental AdhesivesABSTRACT
There are many techniques to overcome the light cured composite related problems including the depth, speed or rate and shrinkage patterns of polymerization. Among them, light transmitting and reflecting matrix, light conducting proximal wedges, incremental placement, use of glass-ceramic inserts and transparent cone, and application of different light exposure patterns could be referred. The goal of this study is evaluation and comparison of the light conducting ability and efficacy of prefabricated CERANA inlay with those made by dental porcelain and three new formulas of bioglass-ceramic and their effects in increasing the bottom hardness of posterior composite resin restorations. In this in vitro study, 90 molars were divided into nine groups of ten samples. Cavities similar to the medium size bur of CERANA kit were prepared in all samples. Forty inlays in the medium size and shape of CERANA with Vita 230 VMK dental porcelain and bioglass-ceramic with three new formulas with MOAZ4, MOAZ5, MOAZ6 codes were made. Four control groups including one bulk and incremental with two different light exposure distances ['0.0 mm to the tooth and 4.0 mm to the composite surface] were considered. All cavities in the control group were restored with A3 Colten composite and 80 seconds light exposure time for one-bulk negative control and testing groups and 2x40 seconds for incremental positive control groups with Coltolux 2.5. After epoxy resin embedding and diamond disk cutting, cooled with water and polishing with 1200 grit Sic paper, samples were tested with micro hardness tester from the top to the depth of four, one millimeter far from each other and 50 microns far from and along the inlays and also counterpart points in control groups. The data were tested with ANOVA and Duncan statistical tests. Along this study, dye penetration was done for all groups for statistical results confirmation. Statistical tests showed that tested groups with Vita 230 VMK, MOAZ6 and MOAZ4 inlays had 20%, 19% and 4% increase in a 4.0 mm depth. The group with CERANA inlays had 1% decrease in respect to the surface. The inlays made by MOAZ5 had the highest light conduction rate because they could cause a 41% increase at the deepest points [4.0mm depth]. In relation to control groups including [C-0] one bulk 0.0 mm, [C+0] incremental 0.0 mm, [C-4] one-bulk 4.0 mm, [C+4] incremental 4.0 mm, a 2%, 22%, 50% and 21% reduction in hardness at 4.0 mm depth in respect to the surface were noticed respectively. Finally, the dye penetration in control and testing groups could support the microhardness testing. Placement of inlays made by MOAZ5 in composite restorations causes a better light conduction and a higher hardness in deeper points of restoration and with monotone and simultaneous curing in different depths of restoration and a higher polymerization and hardness at the flour of restoration causing higher possibility for elimination or reduction of microleakage