Epstein, Edell & Retzer
Method and apparatus for brushing teeth with cyclically rotating brush strokes
 A toothbrush includes a cluster of rotatable bristle tufts disposed between two longitudinally spaced clusters of positionally fixed bristle tufts. The fixed bristles frictionally engage tooth surfaces to oppose longitudinal movement of the brush head in response to longitudinal reciprocation of the brush handle within the head. A rack and pinion convert the longitudinal reciprocation of the handle to oscillatory rotation of the rotatable bristle tufts. 
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inventional inventional additional
Noah
Amit