Muscle
Mylohyoid
Paired support beneath the tongue
High-yield
Mylohyoid separates the sublingual space above from the submandibular space below. Its motor nerve branches from the inferior alveolar nerve before that nerve enters the mandible.
Overview
The two mylohyoid muscles meet beneath the tongue to form much of the muscular floor of the mouth. They link the inner mandible to a central raphe and the hyoid, supporting the oral contents while helping coordinate swallowing.
Reference facts
- Origin
- Mylohyoid line on the inner mandible
- Insertion
- Midline mylohyoid raphe and body of the hyoid
- Action
- Raises the hyoid and floor of the mouth; with the hyoid fixed, can assist jaw opening
- Innervation
- Nerve to mylohyoid from the inferior alveolar nerve (V3)
- Blood supply
- Mylohyoid branch of the inferior alveolar artery, with submental and sublingual contributions
Clinical correlation
A lower-tooth infection may spread above or below mylohyoid depending on where it breaks through bone relative to the muscle attachment. Rapid bilateral floor-of-mouth cellulitis, called Ludwig angina, can involve several connected spaces and threaten the airway.
Frequently asked questions
What does the mylohyoid do?
Raises the hyoid and floor of the mouth; with the hyoid fixed, can assist jaw opening.
What nerve innervates the mylohyoid?
The mylohyoid is innervated by the nerve to mylohyoid from the inferior alveolar nerve (V3).
Where does the mylohyoid attach?
The mylohyoid originates from the mylohyoid line on the inner mandible and inserts on the midline mylohyoid raphe and body of the hyoid.
What is the blood supply of the mylohyoid?
The mylohyoid is supplied by the mylohyoid branch of the inferior alveolar artery, with submental and sublingual contributions.