They're not completely human, but not completely non-human. These dental mannequins lie in the uncanny valley between the two. Dental students use these monstrous simulators to practice their craft.
Some mannequins are even more eerie. This hyperrealistic robot from Japan has a silicone mouth that looks and feels almost like the real thing. It can autonomously turn its head, sneeze, cough, blink, and simulate choking. The robot has speech recognition capability and can hold conversations with dental students.
-via David Thompson