Ancient and evolving craft of horse dentistry

Needham performing dental work at his equine dental school. In the wild, where horses forage all day, grinding their teeth evenly, dental care is unnecessary, but human husbandry causes the need for intervention. — Dylan Cole/The New York Times

YOU are not supposed to look a gift horse in the mouth, checking its age by seeing how worn its teeth are, but people have been examining and fixing horse teeth since 1150 BC, according to archaeologists who found evidence of equine dentistry performed on the Mongolian steppe.

It makes sense: Horses’ mouths, in which they hold their bits, are a key part of their ability to be ridden, but for almost as long, taking care of their teeth has been more an art than a science.