Muscles of the Head and Neck The Muscular

Muscles of the Head and Neck The Muscular System

General Muscle Terminology �Origin: stationary point of attachment �Insertion: movable point of attachment �Action: Anatomical movement that results from the contraction of the muscle

General Info: Facial muscles �Most muscles originate on the surface of the skull and insert into the dermis �Create facial movements and expressions

Frontalis �Action: raises eyebrow, wrinkles forehead

Occipitalis �Action: tenses and retracts the scalp

Masseter �Action: closes mandible Ex: closes mouth during chewing

Temporalis �Action: elevates mandible Ex: clenching your jaw, crushing food

Orbicularis oculi �Action: closes eye Ex: blinking, squinting

Nasalis �Action: compresses nostril

Zygomaticus �Action: draws corner of Ex: smiling mouth upward

Buccinator �Action: compresses cheeks Ex: playing a trumpet, whistling

Orbicularis oris �Action: compresses, purses lips Ex: kissing

Depressor anguli oris �Action: depresses corner of mouth Ex: frowning

Anatomy - Human frontalis temporalis Orbicularis oculi zygomaticus Orbicularis oris platysma masseter buccinator Depressor anguli sternocleidomastoid

Epicranial aponeurosis frontalis occipitalis temporalis Orbicularis oculi nasalis zygomaticus masseter sternoclediomastoid buccinator Orbicularis oris platysma

General Info: Neck muscles �Involved in Swallowing and chewing Moving your head and neck Supporting your head �Anterior neck muscles work on the hyoid bone Suprahyoid muscles (above the hyoid) pull hyoid up Infrahyoid muscles (below the hyoid) pull hyoid down

Sternocleidomastoid �Extends from the clavicles and the sternum to the mastoid region of the skull �Actions: flexion of head, lateral flexion, rotation of head side to side

Platysma �Action: tenses skin of neck, depresses mandible (opens mouth)

Digastric (“two bellies”) �Action: elevates hyoid bone when swallowing; depresses the mandible (opening mouth)

Mylohyoid �Broad/flat muscle provides muscular floor to the mouth and helps press tongue to top of mouth

Sternohyoid �Connects the hyoid bone to the sternum �Action: depresses hyoid bone and larynx

Sternothyroid �Anchors the larynx to the sternum �Action: depresses hyoid bone and larynx

Stylohyoid �Connects the hyoid bone to the styloid process of the skull �Action: elevates hyoid

digastric mylohyoid stylohyoid thyrohyoid omohyoid sternothyroid

Superficial muscles of the neck Sternomastoid Cleidomastoid Sternohyoid Mylohyoid Digastric Masseter TOO DEEP TO DISSECT Stylohyoid Sternothyroid Thyrohyoid

Digastric Mylohyoid Masseter Sternohyoid sternomastoid cleidomastoid

Name the muscle… Frontalis

Name the muscle… Buccinator and orbicularis oris

Name the muscle… Orbicularis oculi

Name the muscle… Platysma

Name the muscle… Orbicularis oris

Name the muscle… Depressor Anguli Oris