IADR Abstract Archives
Cariostatic Effects of Commercial Silver Diammine Fluoride Components on Enamel
Objectives: Silver Diammine Fluoride (SDF) has been used to manage dental caries for decades. Commercial SDF products contain silver and fluoride ions at high concentrations. However the mechanism behind its positive clinical outcome has not been clearly verified. The aim of this study was to investigate the cariostatic effects of the topical application of silver and fluoride ions individually, and in combination, on the demineralisation of human enamel.
Methods: Human permanent molars were sectioned to provide 8 caries-free smooth surfaces. These were polished and then 5mmX5mm windows were created using nail varnish. The samples were demineralised for 4h in 50ml 1M buffered acetic acid pH 4.0 at 37oC. Ion selective electrodes (ISEs) were used to monitor Ca2+ concentration changes in real-time throughout the experiment as a proxy for demineralisation. After 4h, the samples were removed and topically treated with the cariostatic agents shown in Table 1 using a microbrush. The samples were then placed back into demineralisation solutions and Ca2+ release was recorded for a further 4h period. Furthermore, 31P and 19F MAS-NMR was used to assess the interaction of fluoride ions and silver ions with the apatite phase.
Results: The decrease in Ca2+ release following topical application of cariostatic agents is shown in Table 2. The fluoride ions had the greatest efficacy in reducing demineralisation, whereas silver ions had the least effect. 31P NMR results showed that silver reacts with apatite to form Ag3PO4. This was observed following application of SDF, AgF and AgNO3 but not NaF. 19F data showed formation of CaF2 in samples treated with SDF, NaF and AgF.
Conclusions: SDF application inhibits the demineralisation process of enamel, which might be attributed to the establishment of a barrier consisting of Ag3PO4 and CaF2 on the surface. The fluoride ions play the major role of the cariostatic function.
Methods: Human permanent molars were sectioned to provide 8 caries-free smooth surfaces. These were polished and then 5mmX5mm windows were created using nail varnish. The samples were demineralised for 4h in 50ml 1M buffered acetic acid pH 4.0 at 37oC. Ion selective electrodes (ISEs) were used to monitor Ca2+ concentration changes in real-time throughout the experiment as a proxy for demineralisation. After 4h, the samples were removed and topically treated with the cariostatic agents shown in Table 1 using a microbrush. The samples were then placed back into demineralisation solutions and Ca2+ release was recorded for a further 4h period. Furthermore, 31P and 19F MAS-NMR was used to assess the interaction of fluoride ions and silver ions with the apatite phase.
Results: The decrease in Ca2+ release following topical application of cariostatic agents is shown in Table 2. The fluoride ions had the greatest efficacy in reducing demineralisation, whereas silver ions had the least effect. 31P NMR results showed that silver reacts with apatite to form Ag3PO4. This was observed following application of SDF, AgF and AgNO3 but not NaF. 19F data showed formation of CaF2 in samples treated with SDF, NaF and AgF.
Conclusions: SDF application inhibits the demineralisation process of enamel, which might be attributed to the establishment of a barrier consisting of Ag3PO4 and CaF2 on the surface. The fluoride ions play the major role of the cariostatic function.