Dr. Ahmed Fathalla Ibrahim
Jan 04, 2016
Dr. Ahmed Fathalla Ibrahim
SUPRAHYOID MUSCLES
DIGASTRIC MUSCLE:• Origin: by 2 bellies:1.1. Anterior belly:Anterior belly: from digastric fossa of
mandible2.2. Posterior belly:Posterior belly: from mastoid notch• Insertion: both bellies unite in an
intermediate tendon held by a fibrous loop into the hyoid bone
• Nerve supply: 1.1. Anterior belly:Anterior belly: nerve to myelohyoid2.2. Posterior belly: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)
SubmandibularGland
(Superficial part)
MyelohyoidHyoglossus Sublingual
gland
Styloglossus
Stylohoid
DigastricPosterior belly
Hyoid bone DigastricAnterior belly
MANDIBLE
S.P.
SUBMANDIBULAR REGION(Superficial part of submandibular gland is removed)
Deep part ofsubmandibulargland
Myeolohyoid
Hyoglossus
Styloglossus
Sublingualgland
Hyoid bone DigastricAnterior belly
DigastricPosterior Belly
S.P.
MANDIBLE
RELATIONS OF HYOGLOSSUS(Myelohyoid & digastric muscles are removed)
Geniohyoid
Genioglossus
Lingualartery
Externalcarotidartery
Lingualnerve
Styloglossus
Stylopharyngeus
Glossopharyngealnerve
Hypoglossalnerve
Submandibularganglion
Submandibularduct
Hyoglossus
Stylohyoidligament
Deep part ofsubmandibulargland
Sublingual gland
SUBMANDIBULAR REGION
1
2
3
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:
1.1. To submandibular gland:To submandibular gland: fibers are distributed directly to the gland
2.2. To sublingual gland: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