[Long term release of fluoride from selected glass-ionomer cements--in vitro study]

Conventional and resin modified glass-ionomer cements according to their physico-chemical properties are widely used in dental treatment. The main advantages of these materials are chemical bonding to hard dental tissues and high level of fluoride release. The aim of this study was to compare the fluoride release of selected glass-ionomer cements in vitro conditions.

Conventional glass-ionomer cement Ionofil Molar and resin modified glass ionomer cement - Vitremer were examined. Samples of the materials were placed in saline and deionised water. Fluoride concentration measurements were carried out using ORION 9609 electrode, after 1, 3, 24, 48, 72, 168 hours and next every 168 hours (7 days) until 2352 hour (98 days).

Significantly higher concentration level of fluoride released from resin modified cement (Vitremer) was obtained for saline and deionized water than conventional cement Ionofil Molar. Cumulative fluoride release in saline after 14 weeks for Vitremer was 256.87+/-15.77 microg F/mm(2) and for Ionofil Molar 206.61+/-20.01 microg F/mm(2). For both materials the dynamics of fluoride release was the highest within the first 24 hours, and sharply decreased in next intervals.

Resin modified glass-ionomer cement Vitremer released highest amount of fluoride than conventional glass-ionomer cement Ionofil Molar. Similar level of fluoride emission into deionised water and saline was observed.