RESUMEN
Background: The laser therapy has been used as an adjuvant for conventional periodontal disease as they exhibit a bactericidal effect on scaling and root planning by its thermal and photo disruptive effects on the pathogens. This study focuses on the structural and compositional changes induced on the root surfaces of teeth following diode laser (DL) application with increasing quantum of exposure time. Objective: The objective of this study was to evaluate the structural and compositional changes on the root surface of extracted human permanent teeth after application of DLs (810 nm) with varying time interval. Materials and Methods: Twenty samples of single?rooted periodontally compromised extracted teeth were utilized for this study. Root planning was done and the roughness caused by the instrumentation was measured using profilometric analysis. Then, the samples were divided into four groups, with DL application time: Group 1 – laser application for 15 s, Group 2 – laser application for 30 s, Group 3 – laser application for 45 s, and Group 4 – laser application for 60 s. A scanning electron microscope was used to examine the cemental surface and energy?dispersive X?ray analysis software assesses the compositional changes of the teeth in each group. Results: This study reveals that on exposure of DL (810 nm) on the root surface when time of exposure increases, there were relative increases in surface irregularities and charring. There were significant changes in the chemical composition of the tooth surface.
RESUMEN
50 root dentin sections were obtained from 25 extracted premolars and divided randomly into 5 groups of 10 samples each. Except group 1, all the other group specimens were demineralised by immersing in a demineralising solution for 96 hours at 370C. The specimens were then subjected to surface treatment with grape seed extract, silverdiamine fluoride and calcium sucrose orthophosphate complex according to the groups. The samples were stored in artificial saliva during the intervals and subjected to pH cycling and evaluated using SEM-EDAX and the results statistically compared. The tested remineralizing agents showed statistically significant increase in remineralization when compared to the demineralized group. Calcium sucrose orthophosphate showed the highest Ca/Pvalues followed by Silver diamine flouride and grape seed extract
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Prepared three different activated carbons from parts of three different bio-materials viz., Phaseolus trilobus, Leucena leucocephala and Casuarina collected from agricultural field. In the present study phsicochemical and surface characterstics of these prepared carbons have been discussed. For surface characterization FTIR and EDAX methods were used.
RESUMEN
Background & objectives: Cetrimide is a monocationic surfactant, commonly used for disinfection of hospital floors, equipments, for cleansing of burns and wounds, hand wash, etc. We evaluated whether antibiotic resistant (AR) Escherichia coli isolates from hospital settings (nosocomial pathogens) show any evidence of significant reduction in their susceptibility to cetrimide. Also the response of AR E. coli (nosocomial pathogens) to the action of cetrimide was assessed by studying the ultra structural changes induced using transmission electron microscopy (TEM). Methods: A total of 165 clinical samples were screened for isolation of E. coli. Eighty two (49.6%) samples were positive for E. coli. Antibiotic susceptibility testing of E. coli isolates was carried out by Kirby Bauer method to isolate AR E. coli. The randomly selected AR E. coli isolate was treated with different concentrations of cetrimide and minimum inhibitory concentration (MIC) of cetrimide was determined by broth micro dilution method. This same isolate was used for performing time kill assay and TEM study. Results: The test E. coli isolate showed resistance to 12 different antibiotics. The MIC of cetrimide against AR E. coli was 312.5 μg/ml. The ultra cellular structural changes in cetrimide treated AR E. coli revealed vacuole formation, disaxilization of nuclear material, loss of cytoplasmic granularity, bleb formation and cell lysis. Conclusion: Ultra structural changes induced by the action of cetrimide revealed cell damaging changes in the AR E. coli to be dose and time dependent. The results showed that antibiotic resistance does not alter any change in susceptibility of E. coli to cetrimide, which was found to be still an effective disinfectant against a nosocomial pathogen E. coli.