Effectiveness of nanosilver fluoride and silver diamine fluoride in arresting early childhood caries: a randomized controlled clinical trial

Randomized controlled clinical trial in preschool children younger than 4 years with active carious lesions recruited from rural nurseries near Alexandria, Egypt. The study included 180 children randomized to NSF and 180 to 38% SDF, with outcomes assessed over 6 and 12 months.

The active intervention was nanosilver fluoride (NSF), a topical Nano Silver Fluoride formulation containing AgNPs, chitosan, and fluoride. Two drops (10 mg) were applied to each tooth with a microbrush for 2 minutes as a single baseline application. The comparator was 38% silver diamine fluoride (SDF), applied topically to lesions as one drop at baseline and again after 6 months, with petroleum jelly used to protect the lips from staining.

NSF was more effective than 38% SDF for arresting early childhood caries at both 6 and 12 months. Lesion-level caries arrest was 78.4% (691/881) with NSF versus 65.0% (632/972) with SDF at 6 months and 71.3% (628/881) versus 56.3% (547/972) at 12 months, both p < 0.001. Patient-level arrest was also higher with NSF: 61.1% (110/180) versus 40.0% (72/180) at 6 months and 58.3% (105/180) versus 35.6% (64/180) at 12 months, both p < 0.001. NSF caused no black staining and was associated with higher parental satisfaction with children's dental appearance (97.2% vs 76.1%, p < 0.001).

Follow-up was limited to 12 months and the population came from a single rural Egyptian setting, which limits generalizability. The trial involved very young children with active caries, so results may not extend to older children or other clinical contexts. Baseline disease burden differed numerically between groups (median dmfs 5 in NSF vs 11 in SDF), although reported baseline group differences were not significant.