On this day in 1938, DuPont’s new toothbrush went on sale. Doctor West’s Miracle-Tuft was an innovation that shaped dental care. Rather than the pig-hair bristles that people had used before, the new toothbrush used nylon.

Although maybe pig-hair toothbrushes sound weird to modern ears, in a time before products like nylon (which was invented in 1935 by a DuPont chemist) it wasn’t easy to find something that was stiff enough to brush your teeth but soft enough to not completely destroy your mouth.

Some people still brush their teeth with pig-hair toothbrushes today. Although most toothbrushes market still rely on nylon bristles, at least one brand uses the hair from pigs bred for meat. At present, there are no totally plant-based toothbrushes on the market, although manufacturers of brushes with wooden handles say they’re pushing for better options.

All the plastic toothbrushes we go through do add up for the environment. When changed at the recommended rate, that’s three toothbrushes a year per person, writes Chris Jeavans for the BBC. And after they’re discarded, they end up in weird places, like the gullets of albatrosses and other large sea birds. So maybe the idea of brushing with pig isn’t such a bad one after all.

But down through the centuries, many people preferred to use a rag over using hog bristles, reports Pagan Kennedy for The New York Times. For one thing, the bristles were pointy and hard on the gums, even though they softened with soaking. For another, she writes, they were soggy. And they weren’t all that clean. So people would use a rag and some kind of substance—soot, baking soda and salt are three—to clean their teeth.

Even the scientifically advanced Miracle-Tuft didn’t prompt them to change their ways right away, writes Matt Simon for Wired. It took another few years, after America joined WWII, for the nylon-bristled brush to take off. Advertising for the Miracle-Tuft suggested that good health on the home front was essential to victory, while “soldiers returning home from the war brought with them much-improved hygiene habits, which spread quickly around America,” he writes.

Although the history of pig-bristle toothbrushes reaches back to around 1498 in China, the bristle brush spread to Europe and was adopted there. Even Napoleon supposedly used a toothbrush that doesn’t look unlike what we use now—minus the pig.