Tooth Enamel Is the Hardest Substance in the Human Body

Move over, bones! The outer layer protecting our teeth is the hardest thing in our bodies. The next layer down, dentin, is also stronger than bone. The trade-off is that teeth have a very limited ability to heal themselves, unlike bones. You can’t put a cast on a cavity, after all.

Snails Have Thousands of Teeth

Each unassuming snail hides a microscopic secret: between 1,000 and 12,000 tiny teeth protruding from its tongue. They use these teeth to break down parts of their food, and since the teeth are not especially durable, they need to be replaced pretty frequently. This tooth-covered tongue is called a radula, and it's not exclusive to snails. Slugs have them, too, along with some squids.

Not all radula are the same, though. Some predatory snails have venomous radula, and the terrifying-looking Welsh ghost slug has razor-sharp (and teeny-tiny!) teeth for eating worms.

The Earliest Toothbrushes Came From China

Tooth-cleaning goes back thousands of years, with methods including abrasive powder, cloth, and frayed sticks. Bristle toothbrushes emerged in China during the Tang dynasty (618–907 CE); the handles were made from ivory or bamboo. These brushes didn’t catch on in Europe until the 17th century, first in France and later in England.

While toothbrushes evolved in design throughout the 18th and 19th centuries, the materials stayed largely the same. Plastic handles came along in the early 1900s, and nylon bristles followed in 1938.

It Took a While to Get Americans to Brush Their Teeth

It sounds gross, but it’s true: Toothbrushing didn’t become a standard, everyday part of American life until the 1940s. That doesn’t mean all people didn’t brush their teeth — it just wasn’t the standard practice it is today.

The tide started to change in the decades prior, though. In the 1910s, schools started implementing dental hygiene programs like toothbrush drills, in which children practiced brushing their teeth with their teachers. Similar programs visited factories to care for workers’ teeth. This wasn’t just benevolence: Employers hoped their workers would miss fewer days of work due to tooth infections.

With dental hygiene already becoming normalized, one thing set it over the edge: American soldiers during WWII were required to brush their teeth every day, and brought the habit back home with them.

The Oldest Known Dental Filling Is Made of Beeswax

In 2012, scientists used the jaw of a Neolithic man to test out some new X-ray equipment — and in the process, made an exciting discovery. The man, who lived 6,500 years ago in modern-day Slovenia, had a filling made out of beeswax.

Drilling goes back even further than filling, though; archaeologists have found drill holes in teeth from more than 7,500 to 9,000 years ago in a graveyard in Pakistan.

Tooth Pulling Used to Be a Public Spectacle

Before modern dentistry existed, the task of tooth extraction in Britain fell to a strange assortment of professions, including blacksmiths, wigmakers, and a very specific kind of sideshow entertainer. Like snake-oil salesmen, charlatan tooth-drawers traveled to fairs and marketplaces wearing silly hats and sometimes even strings of teeth, eager to rip out teeth for curious spectators. They typically made a grand entrance, sometimes on horseback or with a team of assistants. Loud noises were a key part of the act, both to draw a crowd and to drown out the screams of their “patients.” This continued into the 1800s.

The alternatives, for what it’s worth, weren’t great either. In the 18th and 19th centuries, you could see a “barber-surgeon” (or later, just a surgeon) to get your painful tooth removed with a tooth key, a clawed device that looks a little like a broken corkscrew. All in all, it was not a great time to have bad teeth.

Tooth Fairy? More Like Tooth Mousie

Today, the most common American version of the tooth fairy is a small, whimsical figure, typically female, who checks under our pillows at night for lost baby teeth. But the tooth fairy is an early-20th-century invention, and that particular image rose to prominence right as Disney was releasing animated films featuring kind, gentle, feminine fairies.

The fairy is likely layered on top of a much longer tradition of offering baby teeth to rats and mice — the hope being that the child’s permanent teeth would grow in as strong as a rodent’s. While this practice appears throughout the world, it’s perhaps most common today in Spanish-speaking households. In fact, a specific tooth mouse named Ratoncito Perez emerged in Spanish lore in the 1800s, and spread throughout Latin America in children’s stories. A similar tooth mouse, La Petite Souris, goes back to 1600s France. In some countries, children make it more convenient for the rodent by placing their teeth in or near mouseholes.

The core concept — giving children money in exchange for teeth — dates back to at least the 12th or 13th century, and appears in Norse and Northern European tradition, while other lost-tooth rituals are common throughout the world’s history.

Roald Dahl Had All His Teeth Removed — Voluntarily — at 21

Famed author Roald Dahl was strange in many ways, including his strong opinions about teeth. When he was 21 years old and working at Shell Oil, he decided having teeth was just too much trouble, so he visited a highly regarded dentist in London to have them all taken out and an artificial set created. Five years later, he treated himself to extra-fancy new teeth with the sales from Shot Down in Libya, his first piece of paid writing.

This wasn't especially unusual for British people at the time, but it gets weirder: Dahl became a teeth-removal evangelist. He convinced his mother to have all of hers removed. Then he turned to his four living siblings, none of whom actually went for it; this made him impatient and “foul-mouthed,” according to biographer Donald Sturrock. Finally, he convinced his brother-in-law to go — but to Dahl’s surprise, he never got false teeth to replace them.