Which muscle elevates and retracts the mandible?

Which muscle elevates and retracts the mandible?

• A. Temporalis
• B. Masseter
• C. Medial pterygoid
• D. Lateral pterygoid

Answer: (A)

This question tests understanding of which muscle can both elevate and retract the mandible. The temporalis is able to do both actions: its anterior fibers elevate the mandible to close the jaw, while its posterior fibers retract (pull the jaw back). The other muscles mainly elevate (like the masseter and the medial pterygoid) or contribute to protrusion/depression (like the lateral pterygoid) and do not produce retrusion. So the temporalis is the muscle that accomplishes both elevation and retraction.

This question tests understanding of which muscle can both elevate and retract the mandible. The temporalis is able to do both actions: its anterior fibers elevate the mandible to close the jaw, while its posterior fibers retract (pull the jaw back). The other muscles mainly elevate (like the masseter and the medial pterygoid) or contribute to protrusion/depression (like the lateral pterygoid) and do not produce retrusion. So the temporalis is the muscle that accomplishes both elevation and retraction.