Fountain Brush Sprays Teeth (Oct, 1933)
She really does seem to enjoy doing that.
Fountain Brush Sprays Teeth
A FOUNTAIN toothbrush, which forces a liquid carbonic spray through the bristles, thoroughly cleans the teeth and acts as an atomizer at the same time.The flow of the liquid is controlled by pressing a lever on the container holding enough cleaning fluid for a month. The device is a Norwegian invention.
Carbonic liquid (a component in some soft drinks) is acidic and destroys tooth enamel.