Randomized Clinical Trial on Caries Prevention of Silver Diamine Fluoride

This 30-mo double-blind randomized clinical superiority trial aimed to assess the effectiveness of semiannual application of 38% silver diamine fluoride (SDF) solution in preventing early childhood caries in primary upper anterior teeth. The active comparator was 5% sodium fluoride varnish (FV). The primary outcome was the mean number of new carious tooth surfaces per child at the 30-mo follow-up. Children aged 3 to 4 y were block randomized to receive semiannual application of SDF or FV on their primary upper anterior teeth over a 30-mo period in kindergarten. Parents completed a validated questionnaire to collect information on child oral health-related behaviors and sociodemographic characteristics. In an intention-to-treat analysis, multilevel logistic regression with a generalized estimating equation (GEE) model was performed. At baseline, 730 children with 17,480 sound tooth surfaces were recruited (SDF group, n = 365 children with 8,732 sound tooth surfaces). At the 30-mo examination, 621 children remained (loss to follow-up, 15%; SDF group, n = 307 children with 7,368 tooth surfaces; FV group, n = 314 children with 7,536 tooth surfaces). At the child level, the distribution of new carious tooth surfaces for SDF (mean ± SD, 0.35 ± 1.09) was different from FV (0.54 ± 1.50; Mann-Whitney U test, P = 0.048). At the tooth surface level, GEE analysis showed that tooth surface type influenced new carious tooth surface development, and the caries risk of the SDF group was less than that of the FV group (adjusted odd ratio, 0.61; P = 0.029). In conclusion, semiannual application of SDF is more effective than FV in preventing caries in primary upper anterior teeth for proximal and smooth tooth surfaces (ClinicalTrials.gov NCT04075474).