ANAT3131 Skull and Face

Flashcards for ANAT3131 Lecture Notes

Skull

The skeleton of the head (cranium + mandible).

Neurocranium

Calvaria and cranial base; 8 bones: frontal, ethmoid, sphenoid, occipital, 2 temporals and 2 parietals.

Viscerocranium

15 irregular bones: 3 single (mandible, ethmoid, vomer), and 6 paired bones (maxilla, inferior nasal concha, zygomatic, palatine, nasal and lacrimal).

Nasion

Where the nasal bones articulate with the frontal bones.

Piriform aperture

Anterior opening of the nasal cavity.

Pterion

Union of the frontal, parietal, sphenoid (greater wing) and temporal bones.

Infratemporal fossa

Deep to the zygomatic arch and the mandibular ramus.

Zygomatic arch

Temporal process of zygoma and zygomatic process of the temporal bone

Stylomastoid foramen

For CN VII (Facial Nerve)

Asterion

A star-shaped junction of the parietomastoid, occipitomastoid, and lambdoid sutures.

Lambda

Intersection of the sagittal and lambdoid sutures.

Inion

The most prominent point of the external occipital protuberance.

Hard palate components

Palatine process of maxillae and horizontal plate of the palatine bone

Choanae

Two posterior openings of the nasal cavity.

Foramen magnum

Occipital bone with condyles

Anterior cranial fossa

Anteriorly: frontal (squamous part) bone and laterally, posteriorly: lesser wings of sphenoid, floor: orbital part of the frontal bone and cribriform plate of the ethmoid bone.

Cribriform plate

For CN I

Middle cranial fossa

Anteriorly: lesser wings of sphenoid, posteriorly: petrous part of the temporal bone, laterally: squamous part of the temporal bone and greater wings of spenoid, medially on the floor: body of sphenoid.

Hypophyseal fossa (sella turcica)

A depression for the pituitary gland.

Optic canal

CN II

Superior orbital fissure

CN III, IV, V1, VI

Rotundum

CN V2

Ovale

CN V3

Posterior cranial fossa

Anteriorly: body of sphenoid and petrous part of the temporal bone; posteriorly: occipital bone; laterally: parietal bone.

Internal acoustic meatus

CN VII & VIII

Jugular foramen

CN IX, X, XI & internal jugular v

Hypoglossal canal

CN XII

Platysma

Origin: subcutaneous fascia over pectoralis major and deltoid; Insertion: mandible and skin of neck; Action: wrinkles skin of neck

Orbicularis oris

Origin: maxilla & mandible; Insertion: skin around the mouth; Action: closes mouth, protrudes lips

Levator labii superioris

Origin: maxilla superior to infraorbital foramen; Insertion: modiolus; Action: elevates the upper lip

Zygomaticus major

Origin: zygoma; Insertion: modiolus; Action: Smiling/laughing muscle - moves upper lip up and laterally

Zygomaticus minor

Origin: zygoma anterior to zygomaticus major; Insertion: lateral upper lip; Action: helps elevating upper lip

Depressor labii inferioris

Origin: mandible inferior to mental foramen; Insertion: orbicularis oris; Action: depresses lower lip

Depressor anguli oris

Origin: mandible; Insertion: modiolus; Action: depresses the angle of the mouth

Risorius

Origin: fascia of the parotid gland; Insertion: modiolus; Action: Grinning Muscle - moves the angle of the mouth laterally

Mentalis

Origin: mandible; Insertion: skin of the lower lip; Action: protrudes lower lip

Procerus

Origin: nasal bone & cartilage; Insertion: skin of the bridge of nose; Action: produces transverse wrinkles on the nose bridge

Orbicularis oculi

Origin: frontal bone and maxilla; Insertion: around the orbit; Action: forcibly closes the eyes

Corrugator supercilii

Origin: frontal bone supraorbital ridge; Insertion: eyebrows; Action: draws eyebrows medially & inferiorly

Frontalis

Origin: Galea aponeurosis; Insertion: skin of eyebrows & forehead; Action: elevates eyebrows, wrinkles forehead

Facial nerve (CN VII)

Motor innervation of muscles of facial expression.

Five terminal branches of the parotid plexus

Temporal, Zygomatic, Buccal, Marginal Mandibular, Cervical

Layers of the scalp

Skin, Connective tissue, Aponeurosis, Loose connective tissue, Periosteum