Earthly Pets began the way most of these things do — with a dog whose breath had got bad enough that we stopped letting him near the sofa, and a growing pile of sprays, powders and water additives that did nothing much for longer than an hour.

The brushing advice was sound. It was also useless to us, because our dog had strong opinions about having a toothbrush put in his mouth, and so does most of the country. What we wanted was the thing you could actually do every day without it becoming a fight.