Which item is used to adjust the expansion screw on a removable orthodontic appliance?

• A. Adams crib pliers
• B. Straight hand piece
• C. Acrylic bur
• D. Expansion screw key

Answer: (D)

The item used to adjust the expansion screw is the expansion screw key. This key is designed to fit the head of the screw in a removable orthodontic appliance and is used to rotate the screw, causing the two halves of the appliance to move apart and create expansion. Each activation provides a small, controlled adjustment, as prescribed by the clinician.

The other tools don’t serve this function because they’re for different tasks: Adams crib pliers are used for bending or adjusting wire components of certain appliances, a straight hand piece is a dental drill used for cutting or finishing, and an acrylic bur is used to shape or smooth acrylic material.