Seal or Varnish? A randomised controlled trial to determine the relative cost and effectiveness of pit and fissure sealant and fluoride varnish in preventing dental decay

Main outcome measures: The proportion of children developing caries into dentine (decayed, missing, filled teeth in permanent dentition, i.e. D4-6MFT) on any one of up to four treated FPMs after 36 months. The assessors were blinded to treatment allocation; however, the presence or absence of FS at assessment would obviously indicate the probable treatment received. Economic measures established the costs and budget impact of FS and FV and the relative cost-effectiveness of these technologies. Qualitative interviews determined the acceptability of the interventions. Results: At 36 months, 835 (82%) children remained in the trial: 417 in the FS arm and 418 in the FV arm. The proportion of children who developed caries into dentine on a least one FPM was lower in the FV arm (73; 17.5%) than in the FS arm (82, 19.6%) [odds ratio (OR) 0.84, 95% confidence interval (CI) 0.59 to 1.21; p = 0.35] but the difference was not statistically significant. The results were similar when the numbers of newly decayed teeth (OR 0.86, 95% CI 0.60 to 1.22) and tooth surfaces (OR 0.85, 95% CI 0.59 to 1.21) were examined. Trial fidelity was high: 95% of participants received five or six of the six scheduled treatments. Between 74% and 93% of sealants (upper and lower teeth) were intact at 36 months. The costs of the two technologies showed a small but statistically significant difference; the mean cost to the NHS (including intervention costs) per child was 500 pound for FS, compared with 432 pound for FV, a difference of 68.13 pound (95% CI 5.63 pound to 130.63; pound p = 0.033) in favour of FV. The budget impact analysis suggests that there is a cost saving of 68.13 pound (95% CI 5.63 pound to 130.63; pound p = 0.033) per child treated if using FV compared with the application of FS over this time period. An acceptability score completed by the children immediately after treatment and subsequent interviews demonstrated that both interventions were acceptable to the children. No adverse effects were reported. Limitations: There are no important limitations to this study. Conclusions: In a community oral health programme utilising MDCs and targeted at children with high caries risk, the twice-yearly application of FV resulted in caries prevention that is not significantly different from that obtained by applying and maintaining FSs after 36 months. FV proved less expensive.