Pharmacokinetics of 38% topical silver diamine fluoride in healthy adult volunteers

Abstract

Background: Silver diamine fluoride (SDF) is used topically to prevent or arrest caries. The authors' aim was to characterize the kinetics of silver and fluoride after topical application of SDF.

Methods: Sixteen adults participated in a pharmacokinetics study after the application of 38% SDF to 5 teeth (approximately 50 microliters, estimated 4-11 milligrams per participant). Serum and urine samples were collected over 24 hours after application and were analyzed for silver and fluoride.

Results: Silver serum peak was 0.67 (standard deviation [SD], 0.49) nanograms per milliliter; median time to peak was 3 hours. The estimated elimination half-life of silver was 46 (SD, 26) hours. No silver was recovered in urine. Baseline fluoride serum levels ranged from less than 10 through 50 ng/mL (< 0.01-0.05 parts per million) and fluctuated around baseline after SDF. The 24-hour urinary fluoride was 1.29 (SD, 0.81) mg.

Conclusions: SDF was well tolerated in this study, and no adverse events related to SDF were reported.

Practical implications: This clinical study confirmed that topical application of 38% SDF, in growing use in the United States, is safe and well tolerated in healthy adults.

Keywords: Silver diamine fluoride; clinical study; dental; healthy volunteers.

Figure 1.

Kinetics of silver following application of 38% silver diamine fluoride in healthy adults (n = 16). (A) Observed individual serum silver concentrations (open circles) with average serum silver concentrations (closed circles) and (B) baseline-corrected serum silver concentrations vs. time (average concentration ± standard deviation for each timepoint shown).

Figure 2.

Kinetics of fluoride following application of 38% silver diamine fluoride in healthy adults (n = 16). (A) Mean observed serum fluoride concentrations vs. time (average concentration ± standard deviation for each timepoint shown). Limit of detection was 10 ng/mL (0.01 ppm) for serum fluoride.