Uptake of Fluoride by Glass-Ionomer Dental Cements From a Commercial Fluoridated Mouthwash

Abstract

The ability of glass-ionomer dental cements to take up fluoride from a fluoridated mouthwash has been determined, and shown to vary somewhat with the degree of maturation (ageing). Three commercial conventional glass-ionomer cements were used to produce sets of five discs (6 mm diameter by 2 mm thickness). Discs were aged for 24 h or 1 month at 37°C then placed in 5 cm 3 volumes of commercial fluoridated mouthwash (Plax, ex Colgate Palmolive, Guildford, UK) at a nominal concentration of 112 ppm. Free fluoride ion concentration was measured in samples stored at room temperature for 30 min, 1, 2, 3, 4 and 5 h, using an ion selective electrode. Under these conditions cements were found to take up similar amounts of fluoride at t = 30 minutes, regardless of their age. However, at 5 hours the cements samples matured for 24 hours took up significantly more fluoride than the samples matured for 1 month. In this way it was shown that degree of maturation influenced the ability to take up fluoride without affecting the initial uptake rate. These results suggest that fluoridated mouthwashes may be a valuable source of fluoride for recharging glass-ionomer cements.

Fluoride exchange by glass-ionomer dental cements and its clinical effects: a review

“…Several experimental studies have used solutions of either sodium or potassium fluoride, typically at concentrations of 1000 ppm in fluoride [ 46 , 47 ]. Other experiments have shown that fluoride can be delivered by toothpaste [ 48 ], mouthwashes [ 49 , 50 ] and topically applied fluoride gels [ 51 ]. The fact that fluoride is found in these formulations in association with various counterions suggests that the formulation of the fluoridating medium is relatively unimportant, and that the affinity of glass-ionomers for fluoride is enough to overcome any interaction of fluoride ions with other components of these mixtures.…”