T-t-t-t-toothy Fun THE American classic novelty item (even ahead of the whoopee cushion and rubber vomit, we think) is a set of chattering choppers. Auto-dentures. Invented by Eddy Goldfarb in 1949, a man who made the Toy Industry Hall of Fame ahead of Milton Bradley, these are, not to put too fine a point on it, the sine qua non of gagdom, the ne plus ultra of spring-driven frivolity. Ours are 2-1/2" dia, with a wind-up knob.