1. Posterior belly of digastric
Submandibular Region
Boundaries:
Ant: anterior belly of digastric ms
Post: posterior belly of digastric and stylohyoid ms
Base of the mandible
M a n d i b l e
Posterior belly of digastric
Stylohyoid
Mylohyoid
Hyoglossus
Anterior belly
of digastric
Hyoid bone

2. Main contents of the submandibular region
Salivary glands
Submandibular
Sublingual
Nerves
Lingual nerve (sensory)
Hypoglossal nerve (motor)
Submandibular parasympathetic ganglion
Muscles
Digastric & Stylohyoid
Mylohoid & Geniohyoid
Hyoglossus, Genioglossus & Styloglossus
Vessels
-Facial artery and vein
-Lingual vessels
Sublingual
gland
Anterior belly
of digastric
Mylohoid
Submandibular
Hypoglossal n
ganglion
Lingual n.
Stylohyoid
Post. belly
Hard palate
Palato-glossus
Post. belly
of digastric
Stylopharyngeus
Stylohyoid
Styloglossus
Pharynx
Geniohyoid
Genioglossus
Soft palate
Hyoid bone

3. sternomastoid
Post. belly
of digastric
Tonsillar a.
Ascending palatine a.
Hypoglossal n.
Lingual a.
Ant. belly
of digastric
ECA
Submental a.
mylohyoid
ICA
Facial a.

4. Digastric muscle O: arises by two bellies:
-anterior belly: digastric fossa of mandible
-posterior belly: mastoid notch of temporal bone
I : Intermediate tendon is attached by a fibrous loop to the hyoid bone
N: -anterior belly: mylohyoid nerve (madibular division of trigeminal N)
-posterior belly: facial nerve
A: -elevation of hyoid bone during swallowing
-depression of mandible

5. Important relations of digastric muscle
Superficial relations:
Skin & fasciae and platysma muscle
Posterior belly overlapped by parotid gland and sternomastoid muscle
Anterior belly overlapped by submandibular gland
Crossed by facial v.
Parotid
Sternomastoid
Post belly
of digastric
Facial v.
Submandibular
gland
Mylohyoid
Ant belly

6. Deep relations: Ant. Belly: mylohoid m.
Post. Belly, Crosses the following:
IJV, ICA, ECA
Branches of ECA
(occipital, facial & lingual a.)
X, XI & XII cranial n.
Hyoglossus m.
Mylohyoid
Sternomastoid
S t y l o h y o i d I J V E C A
Post belly
of digastric
X, XI, XII
cranial n.
ICA
Facial &
lingual a
Hyoglossus m
Anterior
belly of
digastric
Occipital a

7. Stylohyoid muscle O: styloid process
I: hyoid bone. Its tendon is perforated by the intermediate tendon of digastric m.
N facial nerve
A elevation and retraction of hyoid bone
Posterior belly
of digastric
Mylohyoid
Stylohyoid
Anterior belly
of digastric
Hyoglossus
Hyoid bone

8. Superficial & deep parts
Submandibular Gland
Position:
Lies in the digastric triangle of the neck, lodged in the submandibular fossa of the mandible
Formed of a large superficial part and a small deep part (the 2 parts are continuous at the posterior border of mylohyoid)
Mylohyoid
Mylohyoid nerve
& vessels
Surfaces & Relations:
Superficial (inferior):
covered by skin, fasciae & platysma
submandibular LN.
crossed by facial vein and cervical branch of facial n.
Lateral: submandibular fossa of the mandible & facial a.
Medial: mylohyoid anteriorly and hyoglossus posteriorly
separated from mylohyoid by mylohyoid nerve & vessels
separated from hyoglossus by:
Styloglossus muscle
Lingual nerve
Submandibular ganglion
Deep part of submandibular gland
Hypoglossal nerve
Suprahyoid vessels.
Superficial & deep parts
of submandibular G.
Hyoglossus
Mylohyoid nerve
& vessels
Hyoglossus
Facial a
Mylohyoid
Submandibular LN
Facial v.
Submandibular G

9. Styloglossus Palatoglossus Lingual n. Hyoglossus Suprahyoid vessels
Hyoid bone
Hypoglossal n.
Submandibular
ganglion
Lingual a.
Genioglossus

10. Submandibular duct: About 5cm long.
Arises from the medial surface of the superficial part
Passes forwards through the deep part on the lateral surface of hyoglossus (between lingual & hypoglossal n)
Runs between genioglossus and sublingual gland
Opens in the floor of mouth on the summit of the sublingual papilla at the anterior end of the sublingual fold
Submandibular
duct
Sublingual G
Lingual n.
Palatoglossus
Hyoglossus
Styloglossus
Genioglossus
Submandibular
ganglion
Suprahyoid
vessels
Hypoglossal n.
Lingual a.
Hyoid
bone

11. Nerve supply: Sensory: lingual n. Sympathetic: plexus around facial a.
Parasympathetic: postganglionic fibres from the submandibular ganglion
(the preganglionic fibres originate from the superior salivary nucleus and run with the facial n., then run into the chorda tympani which joins the lingual n, then leave the lingual nerve to the submandibular ganglion where they relay)
Superior salivary
nucles
Facial n.
Chorda
tympani
Facial a.
Submandibular &
sublingual Gl.
Submandibular
ganglion
Lingual n.
Arterial supply:
Facial & lingual a.
Venous drainage:
Facial & lingual v.
Lymphatic drainage:
Submandibular LN.

12. Mylohyoid muscle Mylohyoid O: mylohoid line of the mandible
I : mylohyoid raphe. The posterior parts of both muscles are inserted into the hyoid bone.
N: mylohyoid n. (from the inferior alveolar branch of the mandibular n.)
A: -elevation of hyoid bone and floor of the mouth
-depression of the mandible
Anterior belly
of digastric
Mylohyoid raphe
Stylohyoid
Mylohyoid
Posterior belly
of digastric
Hyoglossus
Hyoid bone

13. Relations of mylohyoid muscle
Superficial relations:
Skin, faciae & platysma
Anterior belly of digastric
Submandibular gland (superficial part)
Mylohyoid n and vessels
Submental vessels
Submental LN.
Mylohyoid
Anterior belly
of digastric
Mylohyoid nerve
& vessels
Submandibular Gl.

14. Deep relations: Genioglossus & geniohyoid m. Sublingual gland
Lingual a.
Sublingual vessels
Hyoglossus m.
Structures on the lateral surface of hyoglossus:
Styloglossus m.
Lingual n.
Submandibular ganglion
Deep part of submandibular gl.
Submandibular duct
Hypoglossal n.
Suprahyoid a.
Genioglossus
Styloglossus
Hyoglossus
Geniohyoid
Mylohyoid
Hyoglossus
Lingual n.
Submandibular
ganglion
Sublingual
vessels
Genioglossus
Submandibular
duct
Geniohyoid
Lingual a.
Hypoglossal n.
Suprahyoid
vessels

15. Superficial (lateral) relations:
Hyoglossus Muscle
O: hyoid bone (greater horn)
I : side of the tongue
N: hypoglossal n.
A: depression of the tongue
Genioglossus
Styloglossus
Superficial (lateral) relations:
Styloglossus m.
Lingual n.
Submandibular ganglion
Deep part of submandibular gl.
Submandibular duct
Hypoglossal n.
Suprahyoid a.
Covered by:
Mylohyoid muscle
Submandibular gland
Hyoglossus
Mylohyoid
Hyoglossus
Lingual n.
Submandibular
ganglion
Sublingual
vessels
Genioglossus
Submandibular
duct
Geniohyoid
Lingual a.
Hypoglossal n.
Suprahyoid
vessels

16. Deep (medial) relations:
Glossopharyngeal nerve
Stylohyoid ligament
Middle constrictor of the pharynx
Genioglossus
Lingual artery (2nd part)
Stylohyoid ligament
Middle pharyngeal
constrictor
Hyoglossus
Stylohyoid ligament
Middle pharyngeal
constrictor
Genioglossus
Submandibular
duct
Lingual a.

17. Sublingual salivary gland
Lies in the sublingual fossa of the mandible, beneath the mucosa of the floor of the mouth
Raises the floor of the mouth forming the sublingual fold
Relations
Med: genioglossus, submandibular duct, lingual n.
Lat: sublingual fossa
Sup: mucosa of the floor of the mouth
Inf: mylohyoid m.
Sublingual ducts
8-20 small ducts
Open separately on the summit of the sublingual papilla
Arterial supply
Sublingual artery
Venous drainage
Lingual & facial v.
Lymphatic drainage
Submental and submandibular LN
Nerve supply
Sensory: lingual n.
Sympathetic: plexus around facial a.
Parasympathetic: submandibular ganglion

18. Submandibular ganglion
Lingual Nerve
A branch of the posterior division of the madibular nerve
Course
Takes origin in the infratemporal fossa
Joined by the chorda tympani at the lower border of lateral pterygoid
Runs between the ramus of the mandible and medial pterygoid muscle
Enters the floor of the mouth by passing medial to the root of the 3rd molar tooth
Runs on the lateral surface of hyoglossus
Hooks below the submandibular duct
Forms communication with the hypoglossal nerve
Fiber types carried by the lingual nerve:
General sensations from the anterior 2/3 of the tongue
Taste sensation from the anterior 2/3 of the tongue (fibers belong to chorda tympani)
Preganglionic secretomotor fibers to the submandibular ganglion (fibers belong to chorda tympani)
Medial pterygoid
Lingual nerve
Submandibular ganglion

19. Submandibular Ganglion
A small parasympathetic ganglion on the lateral surface of the hyoglossus
It lies between the lingual nerve above and the deep part of the submandibular gland below
Anatomically connected to the lingual nerve
Functionally associated with the chorda tympani (facial nerve)
Roots:
Sensory: lingual n.
Sympathetic: plexus around facial a.
Parasympathetic: fibers from the chorda tympani
(carried by the lingual nerve)
The preganglionic parasympathetic fibers originate from the superior salivary nucleus through the facial nerve, the chorda tympani and the lingual nerve
Branches:
Sensory: carry sensations from the submandibular and sublingual glands
Sympathetic: to the vessels of the submandibular and sublingual glands
Parasympathetic: secretomotor to both submandibular and sublingual glands

20. Genioglossus Muscle Styloglossus Muscle Geniohyoid Muscle Genioglossus
O: superior genial tubercle of the mandible
I : side of the tongue, medial to hyoglossus
N: hypoglossal n.
A: protrusion of the tongue
Styloglossus
Palatoglossus
Styloglossus Muscle
O: styloid process
I : side of the tongue, lateral to hyoglossus
N: hypoglossal n.
A: draws the tongue upwards and backwards
Hyoglossus
Genioglossus
Geniohyoid
Geniohyoid Muscle
O: inferior genial tubercle of the mandible
I : hyoid bone
N: nerve to geniohyoid (fibers from C1 carried by hypoglossal nerve)
A: elevates and draws the hyoid bone forwards

21. Facial artery
Origin, From the front of ECA in the carotid triangle, slightly above the lingual a.
Course and relations
Ascends deep to the posterior belly of digastric and stlyohyoid ms. to reach the digastric triangle
Continues deep to the ramus of the mandible and grooves the posterior end of submandibular gland
Curves downwards between the gland and the mandible
Pierces the deep fascia at the base of the mandible and curves upwards, crossing the anterior inferior angle of the masseter to reach the face
Branches in the neck
Ascending palatine artery
Tonsillar artery
Glandular branches to the submandibular G.
Submental artery
Branches in the face
Inferior labial artery
Superiror labial artery
Lateral nasal artery
Lateral
nasal a
Superior
labial a
Ascending
palatine
Tonsillar
artery
Inferior
labial a
Submental
artery
Facial
artery
ECA
ICA
CCA

22. Lingual artery
Origin: from the front of ECA in the carotid triangle, opposite the tip of the greater horn of hyoid bone
Course and relations, Its course is divided into 3 parts
First part, forms a loop over the tip of the greater horn of hyoid bone
Second part, runs deep to the hyoglossus
Third part (profunda linguae artery)
Ascends on the anterior border of hyoglossus
Runs forwards under cover of the mucosa of the undersurface of the tongue
Reaches the tip of the tongue and ends by anastomosing with the lingual artery of the opposite side
Branches
From the first part
-Suprahyoid artery
From the second part
-Dorsalis linguae arteries
From the third part
-Sublingual artery
-Lingual branches
2nd part of
lingual a.
3rd part of lingual a.
Dorsalis
linguae
1st part of
lingual a.
Sublingual a.
Suprahyoid a.
Hypoglossal n.
Hyoglossus
ECA

23. Lingual artery (2nd part)
Lingual veins:
Profunda linguae vein: receives the sublingual v. and continues backwards (superficial to hyoglossus) as the vena comitans of hypoglossal nerve
Lingual veins: venae comitantes of the 2nd part of lingual artery (deep to hyoglossus), they receive the dorsalis linguae veins.
Lingual vein: is formed at the posterior border of hyoglossus by the union of lingual veins and vena comitans of hypoglossal nerve, and drains into IJV
Dorsal lingual v.
Profunda linguae v.
Sublingual vessels
IJV
Lingual artery (2nd part)
Hypoglossal n.
Vena comitans
of hypoglossal n.