Tooth care varies widely across the world and across history but gets little attention in fiction. In some places, people clean their teeth by chewing on sticks. We have toothbrushes, that used to be made of wood and boar bristle (like some hair brushes) but are now made of plastic. We also have electric toothbrushes and water pik machines that shoot water really hard at our teeth. Just walk into a US grocery store and you'll see a gazillion choices of toothpaste.
In Farscape, they used grubs to clean their teeth, a bit like hippos and birds. I'm sure there was a deliberate science fictional gross factor involved.
Poor tooth health can be associated with lack of money. This recent article talks about the stigma of poor tooth health in the USA: https://aeon.co/essays/there-is-no-shame-worse-than-poor-teeth-in-a-rich-world .
Tooth health is very important. In the US, orthodonture is seen as very important. This isn't the case across the world, but having straight teeth contributes significantly to better tooth health through life in part because it makes regular dental care easier. Removing wisdom teeth is a very common procedure. There is a luxury in not having to think about our teeth.
Tooth health is also a form of public health. The fluoridation of drinking water was a revolution in tooth health, according to both my dentist and this CDC website where you can read up about it: https://www.cdc.gov/mmwr/preview/mmwrhtml/mm4841a1.htm
Generally, main characters don't have tooth problems. Sometimes we see them in movies like Castaway, or Affliction with Nick Nolte, or even in Dances With Wolves, but they are rare. Dr. Who did mention that Shakespeare's breath was horrible. In The Lord of the Rings, Gollum mentions that he has nine (in the video, I misremember it as four). This may be in part because they are so personal to us. It was even difficult for us to start this discussion, because everyone's first reaction to talking about dentistry was to shudder.
George Washington is well known for having only one of his own teeth left by the time he became president, and using dentures made of metal and hippopotamus ivory. It's no wonder that people didn't smile much in pictures of themselves!
Of course, one thing that adversely affected tooth health was the easy availability of refined sugar.
Dentistry dates back to 7000 BCE.
We speculated that one could have aliens or fantasy creatures with rodent-like teeth, who would have to engage in constant gnawing.
Humans also have deciduous teeth, and the dentistry performed on them is different because they are not permanent.
A lot of dentist equipment looks like torture devices, especially in the 1800's. Dentists were also barbers in the early years.
Diet has a huge influence on tooth health. Ancient Egypt generally had good tooth health.
The evil dentist is a trope. We sometimes see endondontists, since root canals are very famous procedures. Orthodontists are even less common. Gold teeth do show up in fiction, however.
Sometimes people put off going to the dentist for so long that by the time they go, the situation is catastrophic. This can be self-fulfilling.
Tooth care in Japan is very different, and teeth are valued differently, even though toothbrushes and toothpaste are largely the same. The dentists I encountered there were much less interested in helping patients keep their teeth than the ones in the US. A Japanese friend of mine who came to the US perceived the US approach as overzealous, a bit like a mechanic who wants your money, and so finds problems where none exist. Snaggle teeth can be considered cute.
Cultural value on teeth changes over time. Back when I was a kid, tooth whitening was not something anyone did. Then people latched onto it, and suddenly there was pressure to have whiter teeth, and to use all kinds of products.
The Maya would inset jade into their teeth.
The Ferengi in Star Trek would sharpen their teeth, and there was an episode where the Klingon Worf buys a tooth sharpener from a Ferengi.
Some human cultures have filed patterns in their teeth or filed them to points. Over a person's lifetime, their teeth will wear down and their gums will recede.
If you are working in a secondary or alien world, think about where references to teeth occur in the language. "Like pulling teeth" "hen's teeth" "long in the tooth" are just some examples from English.
In ancient Japan, married women would blacken their teeth using a dye created by putting iron filings in tea or sake.
Teeth are very personal to us. Should you show them when you smile? That's a very personal question. Should teeth be straight? That can be a significant source of embarrassment. We use super-white teeth as a symbol of vanity, as when you see the gleam coming off someone's teeth in cartoons. Tooth-baring can be a particular form of communication. Tooth pain is also very personal, maybe because it's in an orifice (as Che said) or because teeth are in our head, very close to our perceived seat of consciousness. Our teeth also affect our speech.
The tooth fairy is a very old tradition. In France, children are visited by "la petite souris," or the little mouse (this mouse appears in Rise of the Guardians, but really should have been a female mouse).
What if alien teeth were affected by different substances than ours? That would depend on what kind of bacteria were able to damage them, and what they consumed.
Thanks to everyone who came and discussed teeth with me! There will be no hangout this week, for Thanksgiving, but we will resume the following week.
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