Anatomy II Head & Neck

BY:DR.Yahya Alfarra

CANADIAN BOARD IN DENTISTRY

Parotid region

• Parotid gland ::• Size : it’s the largest salivary

gland & it’s compose of serous acini.

• Shape : it’s wedge shaped , • Site & extension : it lies

between the ramus of Md. & SCM

• It extends : • Upward: to zygomatic arch • Downward: to angle of Md. • Anteriorly: to cover part of

masseter ms.• Posteriorly: to overlap SCM

Parotid duct(stenson’s duct)

• Length : 5 cm long

• Beginning : at the ant. Border of the gland

• End: by opening into the oral cavity opposite the upper 2nd molar tooth

• Opens in the oral cavity opposite to the second upper molar tooth.

Blood supply of P.G

• Arterial supply : small branches from ECA inside the gland

• Venous drainage: into retromandibular V.

• Lymphatic drainage : into deep & superficial parotid lymph node

• Nerve supply of parotid :Sensory : great auricualr N. auriculotemporal N.

Superficial temporal artery

Temporal region

• Temporal fossa

• Infratemporal fossa

• MuSclE OF mastications

Temporal fossa • Boundaries : Sup. Temporal line ……… above Zygonatic arch…………….below Frontal process of zygomatic

bone……………………….ant.• Contents(attachments): 2 superficial Ms of mastications Muscles : a) temporalis Ms. b) masseter Ms• Nerves : a ) deep temporal N.

b)auriculotemporal N.• Vesseles: superficial temporal A.

Infratemporal fossa

• Boundaries: Anteriorly: post. Surface of maxilla Posteriorly : styloid & mastoid

process Medially: lateral pterygoid plate Laterally : coronoid process &

ramus of Md.• Contents:• Muscles : 2 deep Ms of

Mastications a) medial pterygoid Ms. b ) lateral

pterygoid m.• Nerves: a ) Md. N. b ) chorda

tympani c ) Mx. N. • Vesseles : a ) Mx. A. b )

pterygoid plexus of viens

Muscles of masticationsMasseter temporalisMedial

pterygoiodLateral Pterygoid

origin?Floor of temporal

fossa

Arise by 2 head

a)superficial head(Mx.tuberosity)

b) Deep head(med. Surface of lat. Pterygoid plate)

Arise by 2 head

a)Upper head(infratemporal surfaceof greater wing of sphenoid )

b) Lower head(lat. Surface of lat. Pterygoid plate)

Insertion Lateral (outer)surface of ramus of Md.

?.Med. Surface of angle of Md.

Front of neck of Md. & articular disc of T.M.J

Muscles of masticationsMasseter temporalisMedial

pterygoiodLateral Pterygoid

ActionElevate Md. To occlude teeth in mastication

Elevate Md.Elevate Md.Depress Md.

Nerve

supply

Anterior division of mandibular nerve

Anterior division of mandibular nerve

?Anterior division of mandibular nerve

Submandibualr region

• Definition: it’s the regoin between Md. & hyoid bone.

• It contains : • Muscles: digastric, mylohyoid , hyoglossus,

geniohyoid , genioglossus & styloglossus • Salivary gland : submandibualr & sublingual • Nerves : lingual , glossopharyngeal & hyoglossal • Blood vesseles: facial A. & V. , Lingual A. & V. • Parasympathetic ganglion : submandibualr • Lymph nodes : submandibualr group

Muscles of sumandibualr regiondigastricmylohyoidgeniohyoidhyogloss

usgenioglossus

styloglossus

originArise by 2 bellies: ant. Belly: lower border of Md. Close to symphysis menti

Post. Belly: medial surface of mastoid process

Mylohyoid Md.

it.’s a small Ms lying deep(above) to mylohyoid

From genial tubercle(behind symphysis menti of Md.)

Body of hyoid bone

Upper genial tubercle of Md.

Styloid process

insertionInto intermediate tendon that connected hyoid bone

Body of hyoid bone

Upper surface of body of hyoid

Inside tongue deep to styloglossus

Whole length Under surface of tongue

Whole length of side of tongue

Muscles of sumandibualr regoindigastricmylohyoidgeniohyoidhyoglossusgenioglossu

sstyloglossus

Nerve supply

Ant. Belly : N. to mylohyoid a branch of Inferior alveolar N. (from Md. N. )

Post. Belly:

Facial Nerve

N. to mylohyoid a branch of Inferior alveolar N. (from Md. N.)

From C1 via

Hypoglossal N.

Hypoglossa-l N.

Hypoglossal N.

Hypoglossal N.

Action Ant. Belly : opening Md.

Post. Belly:

Retract hyoid bone upward& backward

*support

Floor of

mouth

*elevate

Hyoid Bone

*depress

Md. If Hyoid

Bone is

Fixed(open

Mouth)

*elevate

Hyoid Bone

*depress

Md. If Hyoid

Bone is

Fixed(open

Mouth)

Depress

tongue

Protrude tongue into midline

Retract tongue upward&

backward

Salivary gland

Submandibular gland

• Site & extension: It lies below Md.

• It extends to : Mylohyoid line : a bove Digastric muscle : below Mental foramen : anterior Angle of Md. : posterior • Size: about ½ the size of P.G.• Shape: wedge shape• Structure: it consists of 2

parts,a large superficial part & a small deep part

Submandibular duct

• It’s 5 cm long

• It’s duct open into

the floor of mouth

close to frenulum of tongue.

Blood supply of gland:

• The arterial supply: the gland is supplied by branches of facial & lingual A.

• The viens drain into facial & lingual V.

• Nerve supply :• sympathetic : from plexus arround lingual A. • Parasympathetic: from facial N.

Sublingual gland• Site: beneath tongue• Size: it’s the smallest of the 3

S.G.• Shape: almond-shaped• Relation : Ant. : the gland of the opposite

side Post. : the deep part of

submandibualr gland Med. : genioglossus Ms. , lingual

N. & submand. Duct Laterally: sublingual fossa of Md. Sup. : mucous membrane of

mouth(which elevated to form sublingual fold)

Inf. : mylohyoid Ms.

• Sublingual duct : It opens directly in the floor of mouth on sublingual

fold

• Blood supply : the gland is supplied by branch of facial & lingual A.

The viens drain into facial & lingual V.

• Nerve supply :• sympathetic :from plexus arround lingual A. • Parasympathetic: from facial N.

Nerves OF submandibualr regoin

lingual , glossopharyngeal & hyoglossal N.B. : lingual N. : branch of post. Division of Md. N. in the

infratemporal fossa

• Blood vesseles submandibualr regoin : facial A. & V. , Lingual A. & V.

N.B. Facial A. : Branch of ECAFacial V. : It units ant. Division of retromandibualr V. TO

drain into IJVLingual A. : Branch of ECALingual V. : drain into IJV

Good luck