Title: 1044 - Selective Toxicity of Silver Diamine Fluoride and Silver Nitrate against S. mutans and S. sanguinis In Vitro
Michelle Tsai (Presenter)
University of Iowa College of Dentistry
Jeffrey Banas, University of Iowa College of Dentistry
Fang Qian, University of Iowa College of Dentistry
Objectives: Certain bacteria commonly present in oral plaque, in particular S. mutans, have been linked to an increased risk of dental caries. Others such as S. sanguinis have been associated with healthy oral microbiota. Treatment strategies that target cariogenic strains may have the potential to disrupt the dental decay process and may encompass the greatest capacity for long-term reduction of caries risk. Silver nitrate and silver diamine fluoride both have decades long history of use as topical anti-caries agents. This study sought to investigate the selective toxicity of silver nitrate (SN) and silver diamine fluoride (SDF) against S. mutans and S. sanguinis.
Methods: SN (25%) and SDF (38%) were tested at three different concentrations—1/10 dilution and 1/100 dilution concentration against S. mutans and S. sanguinis grown individually as biofilms in 24-well plates. SDF was also tested at 1% concentration. Statistical analysis consisted of descriptive statistics and a paired-sample t-test (alpha=0.1).
Results: Mean biofilm viability reductions observed for S. mutans treated with 1/100 SDF was marginally significantly greater than that observed for S. sanguinis treated with 1/100 SDF (1.05±0.38 log10 CFU/cm2 vs. 0.43±0.13 log10 CFU/cm2; p=0.0738). Mean biofilm viability reductions observed for S. mutans treated with 1/100 SN was significantly greater than that observed for S. mutans treated with 1/100 SDF (1.78±0.58 log10 CFU/cm2 vs. 1.05±0.38 log10 CFU/cm2; p=0.0360), while there were no significant difference in biofilm viability reductions for any other treatments (p>0.10 for all instances).
Conclusions: The data showed that under certain defined conditions the cariogenic species S. mutans was more sensitive to SDF and SN than the health-related species S. sanguinis. The possibility remains that SDF and SN could have a positive effect on changing the long-term ecology of dental plaque.
The submitter must disclose the names of the organizations with which any author have a relationship, the nature of the relationship, and the clinical or research area involved. The following is submitted: NONE