CRANIAL NERVE 7TH / FACIAL NERVE
INTRODUCTION: - Mixed nerve => motor and Sensory parasympathetic
root.
Motor root supplies muscles of facial expression including;
* Superficial muscles of neck (platysma)
* Auricular muscles
* Scalp muscles
*Muscles that derived from mesoderm in embryonic 2nd pharyngeal arch
Components Location of Cranial Exit Main Actions
1. Somatic nerve cell
2. Visceral bodies
I-Somatic motor Pons *Internal Motor to muscles
Acoustic meatus of facial
*Facial canal expression and
*Stylomastoid scalp, stapedius
foramen stylohyoid and
posterior belly of
digastric
II-Somatic Geniculate
sensory ganglion
III-Visceral motor *Presynaptic:
Pons
*Postsynaptic:
ganglion
Pterygopalatine
Submandibular
ORIGIN:
Brainstem (PONS)
PATHWAY:
CN-VII passes through temporal bone, emerges Cranium through
stylomastoid Foramen located between mastoid & Styloid processes. It
immediately gives off posterior auricular nerve that passes posterior superior
to auricle of ear to supply Auricularis posterior and occipital belly of
occipitofrontalis.
Termination:
, Main trunk of CN-VII runs anteriorly into Parotid gland to form “Parotid
Plexus”.
5 BRANCHES: -
Parotid gives 5 Terminal branches
1. Temporal
2. Zygomatic
3. Buccal
4. Marginal mandibular
5. Cervical
1-TEMPORAL BRANCH
Emerges from superior border of parotid gland
Supply: Auricularis Superior
Auricularis Anterior
Front belly of Occipitofrontalis
Superior part of Orbicularis oculi
2-ZYGOMATIC BRANCH
Passes inferior to eye
Supply: inferior part of orbicularis oculi
3-BUCCAL BRANCH
Passes external to Burcinator
Supply: Buccinator muscle
Upper part of orbicularis oris
Inferior fibers of Levator Labii superioris
4- MARGINAL MANDIBULAR BRANCH
Supply: Risorius and muscles of lower lip + chin after giving branch from
main trunk
5-CERVICAL BRANCH
INTRODUCTION: - Mixed nerve => motor and Sensory parasympathetic
root.
Motor root supplies muscles of facial expression including;
* Superficial muscles of neck (platysma)
* Auricular muscles
* Scalp muscles
*Muscles that derived from mesoderm in embryonic 2nd pharyngeal arch
Components Location of Cranial Exit Main Actions
1. Somatic nerve cell
2. Visceral bodies
I-Somatic motor Pons *Internal Motor to muscles
Acoustic meatus of facial
*Facial canal expression and
*Stylomastoid scalp, stapedius
foramen stylohyoid and
posterior belly of
digastric
II-Somatic Geniculate
sensory ganglion
III-Visceral motor *Presynaptic:
Pons
*Postsynaptic:
ganglion
Pterygopalatine
Submandibular
ORIGIN:
Brainstem (PONS)
PATHWAY:
CN-VII passes through temporal bone, emerges Cranium through
stylomastoid Foramen located between mastoid & Styloid processes. It
immediately gives off posterior auricular nerve that passes posterior superior
to auricle of ear to supply Auricularis posterior and occipital belly of
occipitofrontalis.
Termination:
, Main trunk of CN-VII runs anteriorly into Parotid gland to form “Parotid
Plexus”.
5 BRANCHES: -
Parotid gives 5 Terminal branches
1. Temporal
2. Zygomatic
3. Buccal
4. Marginal mandibular
5. Cervical
1-TEMPORAL BRANCH
Emerges from superior border of parotid gland
Supply: Auricularis Superior
Auricularis Anterior
Front belly of Occipitofrontalis
Superior part of Orbicularis oculi
2-ZYGOMATIC BRANCH
Passes inferior to eye
Supply: inferior part of orbicularis oculi
3-BUCCAL BRANCH
Passes external to Burcinator
Supply: Buccinator muscle
Upper part of orbicularis oris
Inferior fibers of Levator Labii superioris
4- MARGINAL MANDIBULAR BRANCH
Supply: Risorius and muscles of lower lip + chin after giving branch from
main trunk
5-CERVICAL BRANCH
