Fluoride Released from Orthodontic Bonding Material: An In Vitro Evaluation

Enamel demineralization is an undesirable but common complication of orthodontic fixed appliances therapy. The purpose of this study was to test long-term benefits of resin-modified glass ionomer cement (GC Fuji OrthoTM LC) for the prevention of demineralization in patients receiving orthodontic treatment with fixed bonded appliances. 90 healthy extracted premolars without any clinical signs of decalcification were selected. All teeth were cleaned and cut in half buccolingually with a diamond disc. Thus, the control and test specimens were obtained from the same teeth. Orthodontic brackets were bonded with a resin-modified glass ionomer cement. The teeth were divided in 3 groups according to the period of monitoring (1, 3 and 6 months). They were stored in artificial saliva until analyzing. Determination of the fluoride in enamel was done by spectrophotometer. The amount of fluoride in enamel 1 month after the brackets application was significantly higher, after 3 months it was even higher, and after 6 months it was still statistically significantly higher compared to initial values, but lower than the previous 2 time intervals (and remained on a constant level). The results of this in vitro study clearly indicate that fluoride-releasing material used in fixed orthodontic treatment inhibits demineralization of enamel around orthodontic appliances.