A clinical trial of a slow-releasing fluoride device in children.

The objective was to test a fluoride-containing slow-release device in preventing dental caries in children. Accordingly a population of 174 children aged 8 years living in a high-caries, low socio-economic area of Leeds (UK) was assembled. Two slow-release/dissolving glass (SFG) pellets, one with fluoride (F) and one without, were randomly attached to the maxillary molars of the children. Baseline caries as dmft/s, DMFT/S, periodontal disease, plaque and calculus were recorded using standard indices. Unstimulated saliva samples were collected 2 h postprandial for F analysis. All parameters were measured at 6-month intervals for 2 years. There were 132 children completing the trial of whom 63 (test n = 31, control n = 32) still retained the glass devices at the end. Comparison of mean values for gingival health and calculus showed no differences between groups throughout the trial. Mean caries as dmfs at the end of the trial (2.26) was significantly lower for the test (SFG, 2.26) compared with that for the control children (8.41; p < or = 0.001). DMFS was significantly lower at 0.84 and 2.34, respectively (p < or = 0.05). Mean salivary fluoride concentrations were 0.11 and 0.03 mg/l for test and control groups. It was concluded that placement of a glass slow-releasing fluoride device significantly reduced caries incidence in a group of low socio-economic schoolchildren over 2 years.