Cogs (5)
'cogs' is the definition.
(I've seen this before)
This is all the clue.
(Other definitions for teeth that I've seen before include "Canines, for example" , "One may be armed to them" , "Dentition" , "Dentures" , "Structures in the jaw" .)
(Other definitions for gears that I've seen before include "Rages (anag.)" , "Sarge (anag.)" .)