Topical Silver Diamine Fluoride for Dental Caries Arrest in Preschool Children: A Randomized Controlled Trial

Abstract Objective: The Stopping Cavities Trial investigated effectiveness and safety of 38% silver diamine fluoride in arresting caries lesions. Design: Double-blind randomized placebo-controlled superiority trial with 2 parallel groups. Setting: Community settings, Oregon. Participants: 66 preschool children with ≥1 lesion. Intervention: 38% silver diamine fluoride or placebo, applied topically to the lesion. Main Outcomes: The primary endpoint was caries arrest (lesion inactivity, Nyvad criteria) 14 days post intervention. Dental plaque was collected from all children, and relative abundance of all microbes as assessed by metagenomic sequencing was performed for 3 children selected randomly from each group, from 2 lesions and 1 unaffected surface before treatment and again at follow-up. Results: Mean fraction of arrested caries lesions in the silver diamine fluoride group was higher (0.72; 95% CI; 0.55, 0.84) than in the placebo group (0.05; 95% CI; 0.00, 0.16). Mean difference was 0.67; 95% CI: 0.49, 0.80. Confirmatory analysis using generalized estimating equation log-linear regression, accounting for the number of treated surfaces and length of follow-up, indicated the fraction of arrested caries was significantly higher in the treatment group (relative risk, 17.3; 95% CI: 4.3 to 69.4). No harms were observed. Metatranscriptomic sequencing analysis identified no consistent changes in relative abundance of caries-associated microbes, nor emergence of antibiotic or metal resistance gene expression. Conclusions: Topical 38% silver diamine fluoride was effective and safe in arresting cavities in preschool children. The treatment is applicable to primary care practice and may reduce the burden of untreated tooth decay in the population. Trial Registration: ClinicalTrials.gov NCT02536040. Clinical SignificanceIn this clinical trial, 72% of caries lesions were arrested by topical treatment. There were no harms, and surprisingly little change to the bacterial composition of the dental plaque. Silver diamine fluoride was effective and safe in in preschool children. This simple topical treatment is applicable to primary care practice and may reduce the burden of untreated tooth decay in the population.