On which surface is the retentive clasp arm typically located?

On which surface is the retentive clasp arm typically located?

• A. Palatal surface
• B. Occlusal surface
• C. Buccal surface
• D. Mesial surface

Answer: (C)

Retention in an RPD is achieved when a clasp arm engages a tooth undercut to resist dislodgement. That undercut is most predictably found on the buccal surface, so the clasp arm sits on the cheek side and grips the tooth without interfering with chewing or the tongue. Placing retention on the palatal surface would feel intrusive and affect aesthetics, on the occlusal surface it would clash with the biting surface and is usually reserved for rests, and on the mesial surface it can disrupt interproximal contacts and provide less reliable undercut geometry. For these reasons, the buccal surface is the typical location for the retentive clasp arm.

Retention in an RPD is achieved when a clasp arm engages a tooth undercut to resist dislodgement. That undercut is most predictably found on the buccal surface, so the clasp arm sits on the cheek side and grips the tooth without interfering with chewing or the tongue. Placing retention on the palatal surface would feel intrusive and affect aesthetics, on the occlusal surface it would clash with the biting surface and is usually reserved for rests, and on the mesial surface it can disrupt interproximal contacts and provide less reliable undercut geometry. For these reasons, the buccal surface is the typical location for the retentive clasp arm.