The Face, Scalp and Skull

20 April 2010

Face

· Complex combination of multiple organ systems

· Neuromuscular

· Respiratory

· Digestive

· “Gateway to special senses”

Muscles of facial expression

· Important multiple functions

· Communication

· Respiration

· Feeding

· Vocalization

· Protection (primarily of eyes)

Some attachment to bone, but also attachment into subcutaneous connective tissues

Muscles of Facial Expression

· Frontalis

· Orbicularis oculi

· Levator labii suporius

· Zygomaticus major

· Orbicularis oris

· Buccinator

· Depressor anguli oris

· Mentalis

Netter, 2003 pl. 22; Netter, 2006 pl. 26

Nervous Innervation of Face

· Facial nerve (CN VII)

– Motor to all muscles of facial expression

– Five branches

· Trigeminal nerve (CN V)

– Sensory to face

– Ophthalmic (V1): supraorbital, supratrochlear

– Maxillary (V2): infraorbital n.

– Mandibular (V3): mental n.

Facial Nerve

· Temporal

· Zygomatic

· Buccal

· Mandibular

· Cervical

Trigeminal

· Supratrochlear

· Supraorbital

· Infraorbital

· Mental

Clemente 1997; Fig. 736

see Netter, 2003 pl. 20, 21; Netter, 2006 pl. 24, 25

Major blood supply from the external carotid a.

· Facial a.

· Superficial temporal a.

Clemente 1997, Fig. 746

See Netter, 2003 pls. 19, 30, 32; Netter, 2006 pls. 23, 34, 36

Parotid Salivary Gland

Largest salivary gland

Enclosed in parotid capsule

Parotid duct passes anteriorly, to the anterior edge of the masseter muscle to empty into the mouth

Structures within parotid:

facial nerve

retromandibular v.

external carotid a.

Netter, 2003 pl. 20; Netter 2006 pl. 24

Layers of the SCALP

S - skin

C - connective tissue

A - aponeurotic layer

L - loose connective tissue

P - periosteum

The aponeurotic layer spans between the frontalis and the occipitalis muscles. Scalp lacerations through the aponeurosis will gape open due to contractions of the muscle and cause copious bleeding.

From Woodburne & Burkell 1988. Essentials of Human Anatomy, 8th ed. Fig. III-43

Blood supply of scalp

Supraorbital a.

Superficial temporal a.

Posterior auricular a.

Occipital a.

Vessels freely anastamose and run between the Galea aponeurotica and the skin

Netter, 2003 pl. 19; Netter, 2006 pl. 23

Bony Foundation of Face

Fontal

Nasal

Zygomatic

Maxilla

Mandible

Foramina:

Supraorbital foramen

Infraorbital foramen

Mental foramen

see Netter, 2003 pls. 2, 4; Netter, 2003 pls. 2, 4

See handout and link to Tables of Cranial Nerves on the course website.