On 2017 Nov 03, Frank Lippert commented:

It is good to see that more basic, fundamental research on SDF, in particular on enamel caries, is being conducted. The strength of this study is undoubtedly the use of a bacterial caries model. However, the inclusion of appropriate controls, such as silver- and fluoride-only interventions at equimolar concentrations to SDF, would have been advantageous. The observed remineralization effect of SDF could have been simply a fluoride effect, similarly to those observed after a fluoride varnish application. The present study did not allow for the determination of the impact of silver on remineralization, and further, more controlled studies will be required.

On 2017 Nov 03, Frank Lippert commented:

It is good to see that more basic, fundamental research on SDF, in particular on enamel caries, is being conducted. The strength of this study is undoubtedly the use of a bacterial caries model. However, the inclusion of appropriate controls, such as silver- and fluoride-only interventions at equimolar concentrations to SDF, would have been advantageous. The observed remineralization effect of SDF could have been simply a fluoride effect, similarly to those observed after a fluoride varnish application. The present study did not allow for the determination of the impact of silver on remineralization, and further, more controlled studies will be required.