ABSTRACT: This 30-mo randomized clinical trial compared the effectiveness of 2 concentrations (12% or 38%) of silver diamine fluoride (SDF) and 2 periodicity of application (once or twice a year) in arresting cavitated dentin caries in primary teeth. Children aged 3 to 4 y who had at least 1 active cavitated caries lesion were enrolled and randomly allocated into 4 groups for intervention. Group 1 had 12% SDF applied annually (every 12 mo), group 2 had 12% SDF applied semiannually (every 6 mo), group 3 had 38% SDF applied annually, and group 4 had 38% SDF applied semiannually. Clinical examinations were performed semiannually in kindergarten by a single examiner to investigate whether the SDF-treated caries became arrested. A total of 888 children with 4,220 decayed tooth surfaces received SDF application at baseline, and 799 (90.0%) children with 3,790 surfaces (89.8%) were evaluated at the 30-mo examination. The caries arrest rates were 55.2%, 58.6%, 66.9%, and 75.7% for groups 1, 2, 3, and 4, respectively ( P < 0.001). Caries treated with 38% SDF had a higher chance of becoming arrested than those treated with 12% SDF (odds ratio [OR], 1.98; 95% confidence interval [CI], 1.51-2.60, P < 0.001). The interaction between frequency of SDF application and visible plaque index (VPI) score was significant ( P = 0.017). Among those children who received annual SDF application, children with a higher VPI score had a lower chance to have their caries become arrested (OR, 0.59, 95% CI, 0.49-0.72). In conclusion, SDF at a concentration of 38% is more effective than that of 12% in arresting active caries in primary teeth. For children with poor oral hygiene, caries arrest rate of SDF treatment can be increased by increasing the frequency of application from annually to semiannually ( ClinicalTrials.gov NCT02385474).
