A Cluster-Randomized Clinical Trial of Silver Diamine Fluoride vs Atraumatic Restoration in Older Adults

Untreated dental caries, a chronic disease linked to systemic health, is common among older adults due to a lack of dental insurance and affordable dental care. Minimally invasive interventions such as silver diamine fluoride (SDF) and atraumatic restorative treatments (ARTs) have been recommended by the World Health Organization to control caries where evidence is lacking in older adults. This cluster-randomized clinical trial tested the noninferiority of SDF vs ART in caries arrest (primary) and prevention (secondary) at 52 wk. Older adults ≥62 y living in 33 subsidized housing facilities were enrolled at baseline, with follow-up visits at 26 and 52 wk. Participants in the intervention arm received biannual topical application of 38% SDF, and the control arm received ART with glass ionomer cement (+2.5% sodium fluoride varnish). Caries arrest and new caries were determined through examinations conducted by hygienists utilizing criteria from the International Caries Detection and Assessment System. The noninferiority margin was 10% of the effectiveness of the control treatment. Among a total of 568 enrolled participants (intervention: 18 sites, n = 346; control: 15 sites, n = 222), 51% were female and 66% were Black; the mean ± SD age was 69.6 ± 6.8 y. Caries arrest at 52 wk was 88% in the intervention arm vs 92% in the control arm (difference, -0.04; 95% CI, -0.08 to 0.01). After adjusting for sociodemographics, a linear model with generalized estimating equations yielded an estimated treatment difference of -0.05 (95% CI, -0.09 to -0.01). The mean number of new decayed/carious lesions at 52 wk was 0.67 ± 1.72 for the intervention arm and 0.66 ± 1.71 for the control arm (difference, 0.01; 95% CI, -0.31 to 0.32). Results for both outcomes indicated noninferiority of 38% SDF at 52 wk. Findings support the use of a simple topical biannual 38% SDF treatment to control caries in clinical and public health settings, which can be delivered by dental and medical clinicians (ClinicalTrials.gov NCT03916926).