Dental fun with bow drills!
Ever made a fire with a bow drill? Imagine that on your teeth!
While the second image is an early-20th century Inuit tool, ancient tools and texts found in the Indus Valley from ca. 5000-7000 B.C.E. indicate that they had very similar mechanisms (minus the metal tip - theirs would have been stone) to remove rotted sections of the larger teeth. If done proactively, as may have been practiced in the social elite, this would have resulted in much longer-lasting teeth than the common folk.
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