Which muscles collaborate to produce a lateral glide of the mandible?

• A. Masseter and temporalis
• B. Lateral pterygoid and digastric
• C. Medial pterygoid and digastric
• D. Medial and lateral pterygoid

Answer: (D)

Pushing the mandible side to side relies on the pterygoid muscles, which control jaw grinding and lateral translations. The lateral pterygoid helps protrude the mandible and guides the condyle forward, while the medial pterygoid supports the lateral movement by facilitating sideways steering and contributing to the grinding action. When these two muscles work together, they produce the side-to-side glide of the jaw.

Muscles that close the mouth, like the masseter and temporalis, mainly elevate and stabilize the jaw rather than move it sideways, and the digastric opens the jaw rather than drives a lateral glide. That’s why both the medial and lateral pterygoids are needed for this movement.