Acidity, fluoride and silver ion concentrations in silver diamine fluoride solutions: a pilot study

Area of Science:

• Dental materials science
• Caries management
• Biomaterials analysis

Background:

• Renewed interest in silver diamine fluoride (SDF) for managing dental caries in high-risk populations.
• Previous research indicates variability in SDF clinical efficacy and ionic concentrations.
• Discrepancies exist between claimed and actual fluoride (F) and silver (Ag) ion levels in SDF preparations.

Purpose of the Study:

• To quantify the free fluoride and silver ion concentrations in various commercial SDF products.
• To determine the pH of these commercially available SDF preparations.
• To identify potential inconsistencies in SDF formulations impacting clinical use.

Main Methods:

• Analysis of seven global SDF products using ion-selective electrodes for fluoride and optical emission spectrometry for silver.
• pH measurements were conducted using a calibrated pH electrode.
• Comparison of measured ionic concentrations against expected values.

Main Results:

• One 30% SDF product had significantly lower fluoride (16,343 ppm) and higher silver (246,000 ppm) than anticipated.
• Six 38% SDF solutions exhibited mean fluoride of 74,802 ppm (range: 36,457–120,760 ppm) and mean silver of 326,000 ppm (range: 246,000–425,451 ppm).
• All tested SDF solutions were neutral to mildly alkaline (pH 7–10.3).

Conclusions:

• Significant variations exist between claimed and measured fluoride and silver ion concentrations across commercial SDF brands.
• These findings underscore the need for quality control and standardization in SDF product manufacturing.
• Inconsistent SDF formulations may impact treatment predictability and clinical outcomes in caries management.