Muscles of head and neck

Facial muscles:

Epicranius (occipitofrontalis)

Frontal belly

Occipital belly

Galea aponeurotica

Orbicularis oculi

Buccinator

Orbicularis oris

Nasalis

Masticatory muscles

Masseter :

Origin－inferior border and medial surface of zygomatic arch

Insertion－lateral surface of ramus of mandible and angle of mandible

Temporalis :

Origin－temporal fossa

Insertion－coronoid process of mandible

Action : masseter, temporalis --- elevates mandible

—close the mouth

medial pterygoid

lateral pterygoid

Action :

Medial pterygoid—elevates mandible—close the mouth

Lateral pterygoid—pull the head of mandible forwards--- open the mouth

Muscles of neck

Superficial group :

Platysma

Sternocleidomastoid

Origins: manubrium and medial1/3 of clavicle

Insertion: mastoid process of temporal bone;

Actions: acting alone, the head is inclined ipsilateral and the face is rotated to opposite side; acting together, they extend the head.

Suprahyoid muscles :

Mylohyoid

Stylohyoid

Geniohyoid

Action: Elevate (raise) hyoid bone and depress mandible.

Infrahyoid muscles :

sternohyoid

omohyoid

sternothyroid

thyrohyoid

Action: depress hyoid or larynx

The deep cervical muscles: