Purpose: To quantitatively measure the amount of fluoride, hydroxy ion and hydroxyethyl methacrylate (HEMA) released from various light-cured restorative materials.
Materials And Methods: Three resin-modified glass-ionomer cements (RMGI): Photac-Fil Aplicap, Vitremer, and Fuji II LC and two polyacid-modified resin-based composites (compomer): Dyract and Variglass VLC were used in this study. Disc-shaped specimens were made as per manufacturer's recommendations and the surfaces were polished with a 600 grit abrasive paper. Immediately after setting, each disc was immersed into 10 ml of distilled water at 37 degrees C and the eluates were collected after 8- or 24-hour immersion. The concentration of HEMA in the eluate was determined by high performance liquid chromatography. In addition, the concentration of fluoride ion and pH were measured by the respective ion selective electrode.
Results: The RMGIs released the greater amount of fluoride and smaller amounts of HEMA compared to the compomers at both the 8- and 24-hour eluates. Although there were no significant differences in pH of the 8-hour eluates among the restoratives, the pHs of the RMGI were significantly higher than those of the compomers for the 24-hour eluates.
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Macromol Rapid Commun
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Department of Chemistry and Industrial Chemistry, University of Pisa, Pisa, 56124, Italy.
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School of Pharmaceutical Sciences, Guizhou University, Guiyang 550025, China; Guizhou Engineering Laboratory for Synthetic Drugs, Guiyang 550025, China. Electronic address:
Fluoride (F) are common in the environment and are beneficial in moderate amounts but can be harmful at high concentrations, leading to conditions such as fluorosis influenced by reactive oxygen species (ROS), including hypochlorite (ClO). This study introduces PZ-DT, a novel fluorescent probe with a phenothiazine core, designed for the sequential detection of F and ClO. PZ-DT emits orange-red fluorescence with a Stokes shift greater than 200 nm upon F detection, demonstrating excellent selectivity and sensitivity, boasting a quantum yield of 19.
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