Silver Diamine Fluoride in Caries Management
The photos shown here are of someone with rampant caries. The teeth were treated with a substance called silver diamine fluoride. This product kills the pathogenic microorganisms and stops the decay in the tooth. Unfortunately it turns the teeth black in the process, but the teeth can later be restored. The final photo is the start of the restoration of the teeth.
Here is an article from the ADA: