What undercut is typically used with a wrought wire combination clasp?

What undercut is typically used with a wrought wire combination clasp?

• A. 0.01 inch undercut
• B. 0.02 inch undercut
• C. 0.03 inch undercut
• D. 0.04 inch undercut

Answer: (B)

Retention with a wrought wire clasp hinges on engaging the right depth of the tooth undercut. The wire’s flexibility means you don’t need a deep undercut to grab onto the tooth; instead, a moderate undercut provides just enough engagement for secure retention while allowing easy seating and removal without overloading the wire or the tooth. About 0.02 inch is used because it strikes this balance: it offers sufficient resistance to dislodgement without causing excessive friction, distortion, or trauma during insertion or removal. Undercuts that are too shallow (around 0.01 inch) may not provide enough grip for reliable retention, while deeper undercuts (0.03 or 0.04 inch) can lead to excessive binding, patient discomfort, and wear of the clasp. So, 0.02 inch undercut is the typical choice for a wrought wire combination clasp.

Retention with a wrought wire clasp hinges on engaging the right depth of the tooth undercut. The wire’s flexibility means you don’t need a deep undercut to grab onto the tooth; instead, a moderate undercut provides just enough engagement for secure retention while allowing easy seating and removal without overloading the wire or the tooth. About 0.02 inch is used because it strikes this balance: it offers sufficient resistance to dislodgement without causing excessive friction, distortion, or trauma during insertion or removal. Undercuts that are too shallow (around 0.01 inch) may not provide enough grip for reliable retention, while deeper undercuts (0.03 or 0.04 inch) can lead to excessive binding, patient discomfort, and wear of the clasp. So, 0.02 inch undercut is the typical choice for a wrought wire combination clasp.