[In vitro evaluation of different liners in microleakage of class II posterior composite restorations]

Packable composites with high viscosity might not adapt properly to internal surfaces and cervical areas. The aim of this study was to assess the microleakage of class II posterior composite restorations performed using different methods. Ninety proximal cavities were prepared in extracted sound premolar teeth, divided into three groups and filled as follows: 1- packable composite [3M filtek P60], 2-Hybrid composite [Z250] + P60 composite and 3- Resin-modified glass ionomer liner + P60 composite. Afterwards, the samples were immersed in 0.5% Foushin solution and sectioned. Gingival microleakage was then graded. Obtained data were analyzed using paired t-test and analysis of variance. In regard to distal cavities, significant difference was seen between the groups 1 and 3 [P=0.01] as well as groups 2 and 3 [P=0.03]. Comparing microleakage of mesial and distal cavities, there was a significant difference in groups 1 [P=0.003] and 2 [P=0.005]. Based on the findings of this study, application of Z250 composite had no effect on reduction of microleakage of class II posterior composite restorations. Vitremer liner decreased microleakage in dento-gingival margins.

Expression of IL-17 and COX2 gene in peripheral blood leukocytes of vitiligo patients

Vitiligo is a pigmentation disorder in which inflammatory mediators such as cytokines have a pivotal role in disease's pathogenesis. Interleukin 17 [IL-17A] is a proinflammatory cytokine which is involved in the induction of several proinflamatory mediators such as cyclooxygenase 2 [COX2]. The aim of this study was to investigate the gene expression of IL-17 and COX2 in peripheral blood leukocytes of vitiligo's patients. Peripheral blood leukocytes from 15 patients with vitiligo and 15 healthy controls were separated using a gradient density centrifugation method. After total RNA isolation and cDNA synthesis, IL-17 and COX2 gene expression were quantified by real-time polymerase chain reaction [PCR]. There were no significant differences in IL-17 and COX2 gene expression in lymphocytes of patients with vitiligo compared with control group [p<0.05]. However there was an increased IL-17 and COX2 gene expression in neutrophils of patients compared to controls, but it did not reach statistical significance [p=0.05]. We could not find any differences in IL-17 and Cox2 gene expression between clinical diseases subtypes, sex and age. There was a significant correlation between IL-17 and COX2 genes expression in the neutrophils of patients [p=0.00, r=0.80]. Our results showed an increased expression in IL-17 and Cox-2 genes in neurophils of patients with vitiligo. This suggested that these two factors are involved in the inflammatory process. Further studies with a larger sample size might help to establish the role of these factors in the pathogenesis of diseases