The aim of this study was to test a particular type of intra-oral fluoride releasing device (IFRD), designed to release 0.04 mg/day of fluoride over a period of 6 months, using customized holders, in patients receiving orthodontic treatment. Discomfort, holder detachment, plaque accumulation near the device, and the presence of gingivitis, bleeding, white spot lesions, and/or decay was recorded in 76 orthodontic patients (53 experimental and 23 controls) before and after wearing the device for 12 months. The system proved to be easy and quick to use, and did not cause discomfort. There were no significant differences between the treated and the control groups for plaque index, bleeding, or the presence of gingivitis. In addition, no carious and/or white spot lesions occurred during the duration of this study in the test group.