Which muscle depresses the mandible and elevates the hyoid bone during swallowing?

• A. Anterior Digastric
• B. Mylohyoid
• C. Geniohyoid
• D. Stylohyoid

Answer: (B)

Swallowing relies on the suprahyoid muscles to move the hyoid bone upward and forward, which helps elevate the larynx and widen the pharynx for the bolus. The mylohyoid is the floor-of-mouth muscle that contracts to lift the floor of the mouth and the hyoid bone. This upward pull on the hyoid is exactly what you need during swallowing to position the airway and pharynx for safe swallowing. When the hyoid is held up by other muscles, the mylohyoid can also assist in slightly lowering the mandible, contributing to the opening phase of the swallow. Because it directly elevates the hyoid while influencing the mandible's position during swallowing, it fits the described actions best. The other muscles either primarily elevate the hyoid without depressing the mandible (stylohyoid), move the hyoid in different directions or roles (geniohyoid), or mainly depress the mandible with different mechanisms (anterior digastric) rather than combining both actions in the swallowing context.