Horses have a very clear "baby" and "adult" tooth schedule. It’s like a dental calendar that never lies, unless the horse is a master of deception (spoiler: they aren’t). Foals get their first baby teeth—called "milk teeth"—within their first week of life. By age one, they have a full set of temporary chompers.
At around two and a half years, those baby teeth start falling out, much like a human kid losing their baby teeth. The difference? A horse doesn’t put them under a pillow for a fairy; they just chew hay. By age five, every permanent tooth is in, and you’ve got a "full mouth." That’s your baseline starting point.
Reading the Grooves and Galvayne’s Groove
After age five, things get a bit less obvious, but still fun. Look at the lower front incisors—the teeth at the very front. On a young horse (around 5–10 years), the chewing surface has a deep, dark "cup" in the center. As the horse ages, that cup wears down and eventually disappears. By age 10, the cup is usually gone on the lower ones.
Now, here’s the party trick: Galvayne’s Groove. This is a dark, vertical groove that appears on the upper corner incisor. It appears at the gum line around age 10, reaches halfway down by age 15, and extends the full length of the tooth by age 20. After 20, it starts to disappear from the top. It’s like a toothy hourglass.
If you see a full-length groove, you’re looking at a horse who’s earned its senior discount. If the groove is gone entirely? That horse is likely over 25 and has lived a very, very wise life. You might also notice the angle of the teeth changes—they get longer and more slanted, like a gentle Roman arch.
How Can You Tell The Age Of A Horse | Detroit Chinatown
