Silver microwires from treating tooth decay with silver diamine fluoride

Seto, J.; Horst, J. A.; Parkinson, D. Y.; Frachella, J. C.; DeRisi, J. L.

doi:10.1101/152199

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bioRxiv · 10.1101/152199

Silver microwires from treating tooth decay with silver diamine fluoride

Seto, J.·Horst, J. A.·Parkinson, D. Y.·Frachella, J. C.·DeRisi, J. L.

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Abstract

Silver diamine fluoride (SDF) is a brush-on treatment for tooth decay that stops 81% of cavitated caries lesions (dental cavities). Before this innovation, caries was treatable only with operative approaches (dental fillings). SDF-treated lesions harden and become resistant to further decay. We hypothesized that the hardening is due to reaction with silver, rather than classic fluoride-mediated remineralization, because infected dentin is not amenable to remineralization. Using synchrotron microCT with 1.3 m resolution, we observe filamentous densities up to 500 m in length and 0.25-7.0 m in diameter, formed in situ by applying SDF to caries lesions. We show that these \"microwires\" fill voids in the lesion caused by disease, and permeate through surrounding dentinal tubules. Using spectroscopy, we confirm that the chemical composition of the observed microwires is predominantly silver. To our knowledge, this represents the first structural microscale observations resulting from clinical SDF treatment. These novel observations hint at mechanistic explanations for the first clinical method to harden carious dentin besides remineralization. We hypothesize that SDF may not only achieve its antimicrobial functions by biochemical interactions, but also through its inherent ability to integrate into dentin.

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Seto, J., Horst, J. A., Parkinson, D. Y., Frachella, J. C., DeRisi, J. L.. 2017-06-19. Silver microwires from treating tooth decay with silver diamine fluoride. https://doi.org/10.1101/152199

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