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Background: Enterococcus faecalis is the most persistent organism in the root canal which resists most of the intracanal medicaments. There is always a constant attempt to eliminate this endodontic pathogen from the root canal system. Aim: The aim of this study was to evaluate the efficacy of the association of different concentrations of proton-pump inhibitor (PPI) (Lansoprazole) with calcium hydroxide (CH) and chlorhexidine (CHX) against E. faecalis using a broth dilution method. Materials and Methods: E. faecalis was inoculated into brain–heart infusion broth at 37°C for 5 h. The master broth was then treated with CH (Group 1); CH + 2% CHX (Group 2); CH + PPI 6.25 μg/ml (Group 3A); CH + PPI 25 μg/ml (Group 3B); 2% CHX + PPI 6.25 μg/ml (Group 4A); 2% CHX + PPI 25 μg/ml (Group 4B); CH + 2% CHX + PPI 6.25 μg/ml (Group 5A), and CH + 2% CHX + PPI 25 μg/ml (Group 5B). The groups were spectrophotometrically analyzed at 630 nm at 24 h to determine the group with the least optical density. Statistical Analysis: Comparison between the groups was done by the one-way analysis of variance and Kruskal–Wallis test for multiple comparisons. Results: The mean percentage inhibition of E. faecalis by Group 5A (CH + 2% CHX + PPI 6.25 μg/ml) was the highest compared to other groups. The lowest mean value was observed in Group 3A (CH + PPI 6.25 μg/ml) indicating least efficiency. Conclusion: There was a concentration-dependent effect of PPI on CH and CHX against E. faecalis . The maximum efficacy was found when the lower concentration of PPI was associated with CH/CHX mixture.

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In this paper, we propose a holographic scanning based confocal microscope that works in both the reflection and fluorescence modes. Here, the illumination beam is scanned using a reconfigurable binary hologram instead of a usual galvanometer mirror scanner. The reconfigurable hologram is implemented using a liquid crystal spatial light modulator. Two different lasers are used for fluorescence and reflection mode imaging with the phase profile of the illumination beam, derived from each laser, described by the holograms. We demonstrate the working of our microscope in both the modes by imaging a section of tooth specimen stained with a fluorescent dye.

An ideal restorative material should be capable of supplanting the biological, functional, and aesthetic qualities of a healthy tooth structure. There has always been a search for optimal and aesthetically pleasing restorative materials. This study aims to evaluate the surface roughness and colour stability of three nanohybrid composite resins post-exposure to mouth rinse and colouring beverages. MethodsOne hundred and twenty specimens of dimension 10 mm x 8 mm x 1 mm were randomly allocated into three equal-sized groups and fabricated using three different nanohybrid composites (Group A: Filtek Z250 XT, Group B: Tetric N-Ceram, and Group C: Solare Sculpt). Sixty samples, comprising 20 from each group, were examined for colour stability and 60 for surface roughness after exposure to chlorhexidine and coffee. Baseline and post-exposure readings of the surface roughness and colour absorbance of the specimens were obtained by atomic force microscopy and spectrophotometer, respectively. A one-way analysis of variance (ANOVA) test followed by a post hoc Tukey's test and an independent t-test were used for data analysis, considering a p-value<0.05 as significant. ResultsIrrespective of the composite, the surface roughness and colour change were substantially higher in the samples exposed to coffee (p-value<0.01). Filtek Z 250XT showed significantly minor changes in colour and surface roughness, followed by Solare Sculpt and Tetric N-Ceram (p-value<0.05). ConclusionCoffee caused more surface roughness and colour changes compared to chlorhexidine. Filtek 250 XT showed minor changes in colour and surface roughness on exposure to both solutions.