Which muscle inserts at the coronoid process of the mandible?

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

Answer: (A)

The coronoid process is the insertion point for the temporalis, a muscle that elevates the mandible. The temporalis originates from the temporal fossa and the temporal fascia, and its tendon runs to the coronoid process (with some fibers attaching to the anterior ramus). When the temporalis contracts, it pulls the mandible upward, and its posterior fibers can help retract it.

The other muscles involved in jaw movement attach elsewhere: the masseter mainly attaches to the lateral surfaces of the mandible and its angle, the medial pterygoid attaches to the medial surface of the mandible near the angle, and the lateral pterygoid attaches to the neck of the mandible and to the articular disc. None of these insert on the coronoid process.