Comparative Evaluation of Efficacy of Different Irrigating Needles and Devices in Removal of Debris from Apical Third of Root Canal: An In-vitro SEM Study.

BACKGROUND: Irrigants were required to eliminate the microbes and debris from the intraradicular space and must have direct contact with the entire root canal wall. Therefore, different irrigation methods have been proposed to deliver the irrigant as close as possible to the remote areas of the root canal. AIM: The aim of the present study is to evaluate the cleaning efficacy of single-beveled needle, side-vented needle, endovac, and endo-irrigator plus in the removal of debris from apical third of root canal by Scanning Electron Microscope. MATERIALS AND METHODS: Forty single-rooted freshly extracted human permanent mandibular premolars were collected. Root canals were cleaned and instrumented till X2 (25/06) with rotary Protaper Next at working length 1 mm short of the apex. Teeth were randomly divided into four equal groups: Group 1 (n = 10): Endovac, Group 2 (n = 10): Endo irrigator plus, Group 3 (n = 10): Side-vented needle, and Group 4 (n = 10): Single-beveled needle. Irrigation was done with 5.25% NaOCl, followed by 17% ethylenediaminetetraacetic acid. Samples were sectioned and examined under SEM at apical levels. STATISTICAL ANALYSIS: Analysis of variance followed by Tukey's post hoc test was performed. RESULTS: The level of debris removal efficacy is as follows: Endovac > Endo-irrigator plus > Side-vented needle ~ Single-beveled needle. CONCLUSION: Endovac showed the maximum number of debris removal and has better cleaning efficacy in the apical areas of the root canal, followed by Endo irrigator plus, Side-vented needle and Single-beveled needle.

Evaluation of efficacy of combinations of five endodontic sealers with five antibiotics against Enterococcus Faecalis - An in-vitro study.

BACKGROUND: To evaluate and compare in vitro the antibacterial efficacy of five antibiotics when added individually to five endodontic sealers against Enterococcus faecalis (EF). MATERIALS & METHODS: This controlled trial with systematic allocation method was carried out to detect the combined antibacterial activity of five endodontic sealers (Kerr sealer EWT, Endomethasone, AH26, AH Plus, Roekoseal) with five antibiotics regularly used (Amoxicillin, metronidazole, azithromyacin, gatifloxacin, doxycycline) on EF. For each sealerantibiotic combinations, thirty BHI agar plates (15 aerobic and 15 anaerobic) were inoculated with EF, containing five sterile paper discs- three of various sealer- antibiotic combinations, one of sealer alone (positive control) & plain disc as negative control were incubated at 370C for 48 hrs and the zone of inhibition was measured. Data analysis was done by ANOVA and Tukey's post- hoc test using SPSS( version 17). RESULTS: The findings of this study revealed that sealer-antibiotic combination containing amoxicillin had the significant difference (p<0.001) in the mean zone of inhibition compared to other combinations. Metronidazole showed the minimum zone of inhibition among used antibiotics. The sealers in the decreasing order according to their effectiveness on EF were Kerr sealer endomethasone, AH26, Rockseal, AH plus. CONCLUSION: Addition of antibiotics to endodontic sealers enhances their antibacterial activity against Enterococcus faecalis. How to cite the article: Sharma D, Grover R, Pinnameneni PS, Dey S, Raju PR. Evaluation of efficacy of combinations of five endodontic sealers with five antibiotics against Enterococcus Faecalis - An in-vitro study. J Int Oral Health 2014;6(2):90-5.

Enhanced linear and nonlinear optical phase response of AlGaAs microring resonators.

We have constructed and characterized several optical microring resonators with scale sizes of the order of 10 microm. These devices are intended to serve as building blocks for engineerable linear and nonlinear photonic media. Light is guided vertically by an epitaxially grown structure and transversely by deeply etched air-clad sidewalls. We report on the spectral phase transfer characteristics of such resonators. We also report the observation of a pi-rad Kerr nonlinear phase shift accumulated in a single compact ring resonator evidenced by all-optical switching between output ports of a resonator-enhanced Mach-Zehnder interferometer.