Smear layer removal efficacy of different irrigating solutions: A comparative scanning electron microscope evaluation.

Aims: Comparative evaluation of cleaning efficacy of smear layer removal by different irrigating solutions such as 2.5% sodium hypochlorite (NaOCl), 17% ethylenediaminetetraacetic acid (EDTA) with 2.5% NaOCl, 10% citric acid with 2.5% NaOCl and 1% tetracycline Hydrochloride (HCl) with 2.5% NaOCl for smear layer removal in the apical third of root canal. Settings and Design: In vitro material science study. Materials and Methods: Seventy-five single rooted permanent maxillary central incisor teeth were subjected to standardized root canal instrumentation (crown down technique). The teeth were randomly divided into five groups with 15 teeth in each groups: (1) Normal saline (n = 15) (2) 2.5% NaOCl (n = 15) (3) 17% EDTA + 2.5% NaOCl (n = 15) (4) 10% citric acid + 2.5% NaOCl (n = 15) (5) 1.0% tetracycline HCL + 2.5% NaOCl (n = 15). After final irrigation, the teeth were prepared for scanning electron microscope analysis to evaluate the cleaning of apical third of radicular dentine to determine the presence or absence of smear layer. Statistical Analysis Used: The results were analyzed by nonparametric statistical analysis techniques. Kruskal-Wallis test, Mann-Whitney test and Chi-square tests were carried out. Results: There was no significant statistical difference in the efficacy of smear layer removal when 2.5% NaOCl was compared with 17% EDTA with 2.5% NaOCl, 10% citric acid with 2.5% NaOCl and 1% tetracycline HCl with 2.5% NaOCl in apical third of root canals. Conclusions: The present study suggests that irrigating agents, citric acid and tetracycline HCl can be used as an alternative to EDTA for the removal of smear layer in endodontics.

Islet-specific microRNAs in pancreas development, regeneration and diabetes.

Diabetes is a chronic and slowly progressive disease that is presently reaching epidemic proportions in several parts of the world. Multiple aspects including genetic and lifestyle changes have been identified as the key factors leading to the development of type 1 and type 2 diabetes. Although molecular mechanisms underlying the pathogenesis of diabetes remain unclear, recent discoveries in understanding post-transcriptional gene regulation by microRNAs (miRNAs) has opened a new area of research. MicroRNAs have been implicated as new players in pathogenesis as well as complications of diabetes. MiRNAs have been shown to be necessary not only during embryonic development of insulin-producing cells, transcription of (pro-)insulin gene and insulin secretion, but also in development of insulin resistance and diabetes. The present review summarizes the findings related to understanding the role of miRNAs in endocrine pancreas development, pancreas regeneration, islet function and diabetes.