Which arm does not taper in a basic cast circumferential clasp?

Which arm does not taper in a basic cast circumferential clasp?

• A. Reciprocating arm
• B. Retentive arm
• C. Wrought wire arm
• D. Akers clasp

Answer: (A)

In a basic cast circumferential clasp, two arms work together: a retentive arm that engages the tooth’s undercut to provide retention, and a reciprocating arm that sits on the opposite side to provide reciprocal action and resist unwanted tooth movement. The retentive arm is tapered toward its tip to help it slide into and engage the undercut more effectively, increasing retention and guiding insertion. The reciprocating arm, on the other hand, is kept with a relatively uniform cross-section along its length so it maintains consistent contact with the tooth and delivers stable reciprocal resistance as the denture moves. A taper here would alter contact and compromise reciprocity. Therefore, the arm that does not taper is the reciprocating arm.

In a basic cast circumferential clasp, two arms work together: a retentive arm that engages the tooth’s undercut to provide retention, and a reciprocating arm that sits on the opposite side to provide reciprocal action and resist unwanted tooth movement. The retentive arm is tapered toward its tip to help it slide into and engage the undercut more effectively, increasing retention and guiding insertion. The reciprocating arm, on the other hand, is kept with a relatively uniform cross-section along its length so it maintains consistent contact with the tooth and delivers stable reciprocal resistance as the denture moves. A taper here would alter contact and compromise reciprocity. Therefore, the arm that does not taper is the reciprocating arm.