RPD Review Questions

Answer to Question #160


The correct answer is

Correct. The primary purpose of clasps is to resist movement of the RPD occlusally or away from the tissues and teeth---to resist dislodging forces.

Incorrect. Gingival movement is prevented or controlled primarily by rests. Gingival movement may also be prevented to a very minor degree by the rigid portions of clasps but remember, these elements lie on inclined planes and cannot be the primary elements resisting gingival movement of the prosthesis. #2 is definitely not the BEST answer.

Incorrect. Clasps do not function as indirect retainers. Rests and sometimes plating (supported by rests) serve this function.

Incorrect. Clasps have nothing to do with preventing or controlling biting forces on the abutments---unless one made the rather remote argument that rigid portions of clasps help control horizontal components of biting forces. #4 is not the BEST answer.