Transcript 14-submandibular region I

Dr. Ahmed Fathalla Ibrahim
SUPRAHYOID MUSCLES
DIGASTRIC MUSCLE:
• Origin: by 2 bellies:
1. Anterior belly: from digastric fossa of
mandible
2. Posterior belly: from mastoid notch
• Insertion: both bellies unite in an
intermediate tendon held by a fibrous loop
into the hyoid bone
• Nerve supply:
1. Anterior belly: nerve to myelohyoid
2. Posterior belly: facial nerve
SUPRAHYOID MUSCLES
STYLOHYOID MUSCLE:
• Origin: styloid process
• Insertion: hyoid bone
• Nerve supply: facial nerve
SUPRAHYOID MUSCLES
MYELOHYOID MUSCLE:
• Origin: myelohyoid line of mandible
• Insertion: the muscles on both sides
meet in a median raphe extending from
symphysis menti to hyoid bone
• Nerve supply: nerve to myelohyoid
SUPRAHYOID MUSCLES
GENIOHYOID MUSCLE:
• Origin: inferior genial tubercle
• Insertion: hyoid bone
• Nerve supply: ventral ramus of C1
ACTIONS OF SUPRAHYOID
MUSCLES
1. Fixation of hyoid bone (acting with
infrahyoid muscles) during movement
of tongue.
2. Depression of mandible to assist
lateral pterygoid in opening of the
mouth
3. Elevation of hyoid bone to elevate the
floor of mouth & to improve tongue
grip
EXTRINSIC MUSCLES OF
TONGUE
STYLOGLOSSUS MUSCLE (MOST
SUPERFICIAL):
• Origin: styloid process
• Insertion: whole length of side of
tongue
• Action: the muscles on both sides draw
the tongue upwards & backwards
EXTRINSIC MUSCLES OF
TONGUE
HYOGLOSSUS MUSCLE:
• Origin: hyoid bone
• Insertion: posterior half of side of
tongue
• Action: the muscles on both sides
depress the tongue
EXTRINSIC MUSCLES OF
TONGUE
GENIOGLOSSUS (DEEPEST MUSCLE):
• Origin: superior genial tubercle
• Insertion: whole length of side of
tongue
• Action: the muscles on both sides
protrude the tongue
EXTRINSIC MUSCLES OF
TONGUE
PALATOGLOSSUS:
• Origin: soft palate
• Insertion: back of side of tongue
• Action: the muscles on both sides draw
the tongue towards soft palate
NERVE SUPPLY OF EXTRINSIC
MUSCLES OF TONGUE
• ALL MUSCLES ARE SUPPLIED BY
HYPOGLOSSAL (12TH CRANIAL)
NERVE EXCEPT: PALATOGLOSSUS
(BY CRANIAL PART OF ACCESSORY
NERVE)
SUBMANDIBULAR REGION
(Ramus of mandible is removed)
S.
P.
Styloglossus
Hyoglossus
Myelohyoid
Sublingual
gland
Stylohoid
Submandibular
Gland
(Superficial part)
Digastric
Posterior belly
Hyoid bone
M
A
N
D
I
B
L
E
Digastric
Anterior belly
SUBMANDIBULAR REGION
(Superficial part of submandibular gland is removed)
S.
P.
Styloglossus
Sublingual
gland
Hyoglossus
Myeolohyoid
M
A
N
D
I
B
L
E
Deep part of
submandibular
gland
Digastric
Posterior Belly
Hyoid bone
Digastric
Anterior belly
RELATIONS OF HYOGLOSSUS
(Myelohyoid & digastric muscles are removed)
Styloglossus
Stylopharyngeus
Lingual
nerve
Submandibular Deep part of
submandibular
ganglion
gland
Sublingual
gland
Submandibular
duct
Stylohyoid
ligament
Glossopharyngeal
nerve
Hyoglossus
Genioglossus
Hypoglossal
nerve
External
carotid
artery
Lingual
artery
Geniohyoid
SUBMANDIBULAR REGION
1
3
2
LINGUAL ARTERY
• BEGINNING: from anterior aspect of external
carotid artery, in the carotid triangle,
opposite the tip of greater cornu of hyoid
bone
• COURSE: has a tortuous course, divided into
3 parts:
• FIRST PART: forms a loop crossed by
hypoglossal nerve
• SECOND PART: runs along upper border of
greater cornu of hyoid bone, deep to
hyoglossus
• THIRD PART: ascends along anterior border
of hyoglossus & runs along the under
surface of tongue to reach its tip &
anastomoses with artery of opposite side
BRANCHES OF LINGUAL ARTERY
• FROM FIRST PART: Suprahyoid artery: runs
along upper border of greater cornu of hyoid
bone, superficial to hyoglossus, supplying
adjacent muscles
• FROM SECOND PART: Two dorsal lingual
arteries: supply dorsum of tongue
• FROM THIRD PART: Sublingual artery:
supplies sublingual gland & mucous
membrane of floor of mouth
• N.B.: VEINS CORRESPONDING TO
BRANCHES OF LINGUAL ARTERY UNITE TO
FORM A SINGLE LINGUAL VEIN THAT
DRAINS INTO INTERNAL JUGULAR VEIN
SUBMANDIBULAR GANGLION
• It is a small parasympathetic ganglion lying
superficial to hyoglossus & is connected to
lingual nerve by 2 roots (anterior &
posterior)
• Origin of fibers: superior salivary nucleus in
pons
• Preganglionic fibers:
1. Runs along chorda tympani branch of facial
nerve
2. Chorda tympani transmits fibers to lingual
nerve branch of mandibular nerve
3. Lingual nerve transmits fibers to ganglion
through posterior root
SUBMANDIBULAR GANGLION
• Postganglionic fibers:
1. To submandibular gland: fibers are
distributed directly to the gland
2. To sublingual gland:
• Fibers pass along anterior root to
lingual nerve again
• Lingual nerve transmits fibers to
sublingual gland
RELATIONS OF HYOGLOSSUS
SUPERFICIAL (LATERAL):
• 2 MUSCLES: myelohyoid, styloglossus
• 2 NERVES: lingual, hypoglossal
• 2 GLANDS: superficial & deep parts of
submandibular glands
• 2 SUBMANDIBULAR: duct & ganglion
RELATIONS OF HYOGLOSSUS
DEEP (MEDIAL):
• 1 MUSCLE: genioglossus
• 1 NERVE: glossopharyngeal
• 1 VESSEL: Lingual
• 1 LIGAMENT: stylohyoid