Structure and Development
- The mylohyoid muscle is flat and triangular.
- It is situated immediately superior to the anterior belly of the digastric muscle.
- It is a pharyngeal muscle derived from the first pharyngeal arch.
- The mylohyoid muscles form a muscular floor for the oral cavity.
- The two mylohyoid muscles arise from the mandible at the mylohyoid line.
- The mylohyoid muscles are derived from embryonic mesoderm, specifically the first pharyngeal arch.
Nerve Supply
- The mylohyoid muscle is supplied by a branch of the mandibular nerve, the inferior alveolar nerve.
- The mylohyoid nerve is a branch of the inferior alveolar nerve.
- The mylohyoid nerve provides motor supply to the mylohyoid muscle.
Variations
- The mylohyoid muscle may be united to or replaced by the anterior belly of the digastric muscle.
- Accessory slips to other hyoid muscles are frequent.
- The median raphe between the two mylohyoid muscles may be absent.
- Accessory mylohyoid muscles with the same attachments, nerve supply, and function can be present.
- The mylohyoid muscle may be split into an anterior and posterior portion.
Function
- The mylohyoid muscle elevates the hyoid bone and the tongue.
- It is important during swallowing and speaking.
- It can depress the mandible if other muscles keep the position of the hyoid bone fixed.
- It reinforces the floor of the mouth.
None
The mylohyoid muscle or diaphragma oris is a paired muscle of the neck. It runs from the mandible to the hyoid bone, forming the floor of the oral cavity of the mouth. It is named after its two attachments near the molar teeth. It forms the floor of the submental triangle. It elevates the hyoid bone and the tongue, important during swallowing and speaking.
| Mylohyoid muscle | |
|---|---|
 Muscles of the neck seen from the front (mylohyoid muscle colored in bright red) | |
 Surface anatomy of the neck seen from the front (mylohyoid muscle labeled at right, second from top) | |
| Details | |
| Origin | Mylohyoid line (mandible) |
| Insertion | Body of hyoid bone and median ridge |
| Artery | Mylohyoid branch of inferior alveolar artery and submental artery of facial artery |
| Nerve | Mylohyoid nerve, from inferior alveolar branch of mandibular nerve |
| Actions | Raises oral cavity floor, elevates hyoid, elevates tongue, depresses mandible |
| Identifiers | |
| Latin | Musculus mylohyoideus |
| TA98 | A04.2.03.006 |
| TA2 | 2165 |
| FMA | 46320 |
| Anatomical terms of muscle | |
mylohyoid muscle (plural mylohyoid muscles)
