Effect of diamine on caries lesion of human

Yihong Li1, DDS, MPH, DrPH Simone Duarte1, DDS, PhD Timothy G. Bromage2, PhD 1Department of Basic Science 2Department of Biomaterials & Biomimetics Silver Diamine Fluoride (SDF, 38%)

• A transparent solution • High content of silver and fluoride [24.4-28.8% (w/v) Ag and 5.0-5.9% fluoride, at pH 10] • Cariostatic topical agent with a caries treatment efficacy of ~70-83% in deciduous teeth and ~60% in permanent teeth • The procedure is non-invasive, pain-free, convenient, time- saving, and low-cost • Does not require complex training of the health professional to apply • Benefit for patient management • With a great potential as an alternative treatment to costly preventive methods with limited resources

Downsides of 38% SDF or 10% AgNO3 Silver Diamine Fluoride (SDF)

Gap of knowledge related to the mechanisms: • Previous assumptions on silver and fluoride elements • 254,709 ppm silver and 44,860 ppm fluoride ions in 38% SDF solution • Laboratory experiments ( blocks) • Artificial mouth • Single bacterial species

Analysis of deciduous caries lesion treated with 38% SDF

(A) Image of a carious lesion treated (B) Images of dentinal tubules in with SDF. Insert: Lesion surface lined longitudinal section with silver with silver precipitate. precipitation and penetration. Insert: Silver precipitates are appearing as highly dense (white) particles within tubules. Silver penetration in carious dentin

Dentin (µm) 514.91 572.27 1022.28 1291.27 AVG 850.18

300 µm

The electron-scanning electron microscopy examination clearly demonstrated that silver precipitation was positive in demineralized enamel rods and dentin tubules. Silver precipitation occurred range of 102.87 to 1,509.42 m into the enamel or dentinal tubules. The effect of SDF on formation

The SDF-treated teeth showed a significant reduction in S. mutans viability and the biofilm formation compared that to untreated control teeth. The effect of biofilm formation

The FV-treated teeth showed a reduction in S. mutans viability. However, there were not significant differences in biofilm formation between the teeth treated with or without FV. Biofilm analysis, SDF vs. FV

S. mutans formation S. mutans viability

**

** Summary of our preliminary findings

• Application of 38% SDF was found to form a dense precipitate layer on the deciduous tooth surface, with the greatest localization within demineralized structures of the caries lesion.

• The antimicrobial function of SDF is more effective than FV in inhibiting S. mutans viability and biofilm formation in deciduous teeth with carious lesions. QUEST mission – elucidate the etiology of and reduce ECC/S-ECC in AI/AN children

sealant ECC fluoride

intervention

treatment effectiveness sustainability Etiology of dental caries

Tooth Diet

HAS-ECC

Caries

Microbiota DDE-ECC study in Shanghai, China, 2016

N = 1,366 Age: 3-6 year DDE-/ECC - Sound

N = 1,366; Age: 3-6 year N = 1,366 DDE+/ECC- DDE without active caries DDE+/ECC+ DDE with caries

N = 1,366 QUEST – How does SDF affect on DDE+ECC?

sealant fluoride SDF? intervention DDE treatment ECC

effectiveness sustainability QUEST – research responsibilities • The mode of action for arresting caries progression and preventing new caries, whether chemical, physical, mechanical, or antibacterial, needs further study. • SDF safety issues for very young children.