Abstract
BACKGROUND: This umbrella review comprehensively appraised evidence for silver diamine fluoride (SDF) to arrest and prevent root and coronal caries by summarizing systematic reviews. Adverse events were explored. METHODS: Following Preferred Reporting Items for Systematic Reviews and Meta-analysis (PRISMA) guidelines, PubMed, Embase, Cochrane Library, PROSPERO register and Joanna Briggs Institute Database of Systematic Reviews were searched for systematic reviews investigating SDF for caries prevention or arrest (1970-2018) without language restrictions. Systematic reviews were selected, data extracted, and risk of bias assessed using ROBIS by two independent reviewers, in duplicate. Corrected covered area was calculated to quantify studies' overlap across reviews. RESULTS: Eleven systematic reviews were included; four focussing on SDF for root caries in adults and seven on coronal caries in children. These cited 30 studies (4 root caries; 26 coronal caries) appearing 63 times. Five systematic reviews were of "low", one "unclear" and five "high" risk of bias. Overlap of studies was very high (50% root caries; 17% coronal caries). High overlap and heterogeneity, mainly comparators and outcome measures, precluded meta-analysis. Results were grouped by aim and outcomes to present an overview of direction and magnitude of effect. SDF had a positive effect on prevention and arrest of coronal and root caries, consistently outperforming comparators (fluoride varnish, Atraumatic Restorative Treatment, placebo). For root caries prevention, the prevented fraction (PF) was 25-71% higher for SDF compared to placebo (two systematic reviews with three studies) and PF = 100-725% for root caries arrest (one systematic review with two studies). For coronal caries prevention, PF = 70-78% (two systematic reviews with two studies) and PF = 55-96% for coronal caries arrest (one systematic review with two studies) with arrest rates of 65-91% (four systematic reviews with six studies). Eight systematic reviews reported adverse events, seven of which reported arrested lesions black staining. CONCLUSION: Systematic reviews consistently supported SDF's effectiveness for arresting coronal caries in the primary dentition and arresting and preventing root caries in older adults for all comparators. There is insufficient evidence to draw conclusions on SDF for prevention in primary teeth and prevention and arrest in permanent teeth in children. No serious adverse events were reported.