Search

Background: The long-term success of root canal therapy depends on the effective debridement and removal of smear layer and debris from the canal. Root canals with difficult anatomy and complex systems pose great challenge to achieve this. Mechanical therapy alone cannot achieve this goal, various intracanal chemicals also have their own limitations along with the difficulty in reaching the farfetched and difficult areas, and hence, introduction of ultrasonic bypass system has been a boon for the endodontic therapy. Objectives: The aim of this study is to compare the various root canal medicaments along with ultrasonic bypass system in effectively cleaning the debris and smear layer from the various parts of the root canal system. Materials and Methods: Forty single-rooted anterior maxillary and mandibular human teeth were collected for this study, after disinfection, they were sectioned into three equal parts coronal, middle, and apical and these parts were later studies under SEM (Scanning Electron Microscope) and scoring as per the scoring criteria set before the study was done and results were then compared statistically. Results: Group with both ethylenediaminetetraacetic acid (EDTA) and NaOCl with ultrasonic bypass system was the most effective one, when compared with sterile water, NaOCl + ultrasonic bypass system, EDTA + ultrasonic bypass system. NaOCl + ultrasonic bypass system was more effective as compared with the EDTA + ultrasonic bypass system. Conclusion: Ultrasonic bypass system is a useful tool for debris and smear layer removal from a root canal system, but its effectiveness increases when both EDTA and NaOCl are used along with it. [ABSTRACT FROM AUTHOR]

The microstructures of the carapaces of the spider crabs Schizophrys dahlak and Hyastenus hilgendorfi were examined under both scanning and transmission electron microscopes. Image analyses of the cross-sectioned carapaces showed that both species have a hierarchical microstructure with three well-defined layers. The two innermost layers (exocuticle and endocuticle) consist of stacked fibers arranged in a twisted plywood fashion producing a "Bouligand structure". They have a similar structure but different thicknesses and height of the stacks. The cuticles are inter-stitched with pore canals of varying width between the studied species, running transversely to the layered structure. This variation in the width of the pore canals in the two species seems to be proportional to the size of the carapace and its surface area. [ABSTRACT FROM AUTHOR]

The article offers information on study on foraminifera Nummulites (N.) vredenburgi found in Kutch, western India. Topics discussed include use of scanning electron microscope (SEM) to show pores and canals in N. vredenburgi, modification in the lateral part of N. vredenburgi and use of it in functional analysis of N. vredenburgi, and light microscope examination of the dimorphic tests of N. vredenburgi to reveal the granulated surface of protists.