PubMed · 5033284
The source did not provide an abstract. Follow the original record for more information.
Explore connections, maps & timelines
E Berman, K McKiel. 1972. Is that toothpaste safe?. https://doi.org/10.1080/00039896.1972.10666137
Cite the original work for its findings. Save a collection to share your selection of sources.
KEEP EXPLORING
Toothbrush bristles with sharp edges have been postulated to represent a greater threat to dental tissues than end-rounded bristles. This study evaluated the effect of both in vivo and laboratory use on bristle wear rate, tip geometry and in vitro abrasivity. Three soft manual brushes (Oral-B P40, Crest Complete and Butler GUM) and one powered brush (Rota-dent) were tested. The results of this study show that the wear rate varied directly with brushing load and amount of dentifrice, and inversely with bristle diameter. Despite the initial geometry, a flat tip with rounded rims was typically observed after only 30 minutes of manual or Rota-dent brush use. There was no statistical difference in in vitro abrasion for new brushes versus used brushes.
The method is based upon the reaction between fluoride ions and the coloured complex of Fe(III) with methyl salicylate to form the stable, colourless hexaflouride complex of iron. The conditions of the method (pH, time and combination ratio) were studied and a standard curve was obtained for 0.01-0.08 mg NaF ml-1, at 525 nm. A study was conducted on interference with complexing anions of Fe(III), cations that react with fluoride ions and with common ingredients of dosage forms and dental preparations. The method was validated and the results showed good precision (100.16 +/- = 2.33%) comparable with that of other analytical methods. Good results were obtained in the spectrophotometric determination of fluoride ions in a stomatological gel and in a toothpaste.
The fluorescence of tin(IV) complexed by 8-hydroxyquinoline-5-sulfonic acid (8-HQSA) has been studied in both aqueous and hydroorganic (acetate buffer and dimethylsulfoxide) media. Several experimental parameters such as pH, DMSO/water ratio and reactant concentration have been investigated to increase the fluorescence of the tin(IV)-8-HQSA complex. A linear relationship between tin(IV) concentration and fluorescence intensity was observed between 1.7 and 20 microM). Mechanistic and quantitative studies in the presence of surfactants have been performed. Judiciously selected micellar media permitted solubilisation and quantitation of tin(IV) as well as dibutyltin compounds. A linear relationship between concentration and fluorescence intensity was found for mono-, di- and tributyltin with detection limits of 0.1 microM, 0.7 microM and 1 microM, respectively.