submandibular region anatomy suitable for BDS classes

1. Submandibular region
and suprahyoid
muscles
Department of Anatomy
VIMS &RC

2. Submandibular region
• The region extends from the under cover of the body of the mandible to
hyoid bone
• Contents are
1. Submandibular gland
2. Sublingual gland
3. Suprahyoid muscles
4. Extrinsic muscles of tongue
5. Lingual nerve
6. Submandibular ganglion
7. Lingual artery and facial artery

3. Salivary glands

4. Submandibular gland
• One among the paired salivary glands
• Walnut in appearance
• It’s a mixed salivary gland
• Placed in digastric triangle
• Partially occupying the submandibular fossa of mandible
• It has a large superficial part and a small deep part
• Continues around the posterior border of mylohyoid muscle

6. Parts
• Superficial part has
• Anterior end –extends up to the anterior belly of digastric
• Posterior end –stylomandibular ligament
• Inferior surface –investing layer of deep cervical fascia
• Medial surface - investing layer of deep cervical fascia
• Lateral surface –submandibular fossa of mandible

7. Relations
• Relations of inferior surface
• Skin
• Superficial fascia
• Platysma
• Deep cervical fascia
• Common facial vein
• Cervical part of the facial nerve
• Submandibular lymph nodes

9. Relations
• Relations of lateral surface
• Submandibular fossa
• Medial pterygoid muscle
• Facial artery –loops downwards and forwards between the bone and
the gland ,winds around the anterio-inferior angle of the masseter
before appearing on the face

10. Relations
• Medial surface
• Anterior pat -Rests on mylohyoid muscle
• Separated by mylohyoid muscles and nerves
• Posterior part-Styloid apparatus
• Posterior belly of digastric muscle
• Glossopharyngeal nerve
• Middle constrictor of pharynx
• Intermediate area –
• hyoglossus muscle
• Lingual nerve
• Submandibular ganglion

11. Relations
• Deep part
• Extends from the interval between the mylohyoid and hyoglossus
muscle to the sublingual salivary glands
• Related to
• Medially -hyoglossus muscle
• Laterally-mylohyoid muscle
• Above –lingual nerve and submandibular ganglion
• Below –hypoglossal nerve

12. • Blood supply –
• Branches of facial artery and lingual artery
• Corresponding veins drain to Internal jugular vein
• Lymphatic drainage
• Submandibular lymph nodes –jugulo-digastric lymph nodes

13. Submandibular duct
• Wharton’s duct
• 5 cm long
• Starts -Middle of the deep surface of the superficial part of the gland
• Direction-Upward and backward ,forward and upward
• Opens -On the floor of the mouth at the sublingual papillae on each
side of the frenulum linguae

14. Submandibular duct

15. Nerve supply-preganglionic fibres
Superior
salivatory
nucleus
Facial nerve
Chorda
typmani nerve
Lingual
nerve(post
root )
Submandibular
ganglion

16. Nerve supply –post ganglionic fibres
Submandibular
ganglion
Lingual nerve
(ant root)
Submandibular
Sublingual
glands

17. Sublingual gland
• Smallest
• Located in the floor of the mouth
• Lodges the sublingual fossa
• Between the mucous membrane and mylohyoid muscle
• Ducts -8-20 small ducts
• Most of them opens separately on the floor of the mouth on the
sublingual fold (Ducts of Rivinus )
• Some of them unite to form sublingual duct and joins the
submandibular duct (Ducts of Bartholin )

19. Sublingual gland
• Blood supply –sublingual and submental arteries -facial artery
• Lymphatics- submental group of lymph nodes
• Nerve supply –same as submandibular gland
• Relations –
• Infront -Meets the opposite side gland at symphysis menti
• Behind –deep part of submandibular gland
• Above –covered by mucous membrane of mouth forming the sublingual
fold
• Below –mylohyoid muscle
• Laterally-sublingual fossa
• Medially –rests on genioglossus

20. Applied anatomy
• The submandibular gland may enlarge because of the obstruction of
its duct due to a calculus or by tumour
• Sialography – visualization of the duct system of the major salivary
gland dusts in x ray after injecting radio opaque dye
• Ranula –cystic swelling of the floor of the mouth due to obstruction
of the ducts of sublingual gland

22. Supra hyoid muscles
• Geniohyoid –Genial tubercle –c1 via hypoglossal nerve
• Anterior belly of digastric-digastric fossa –mylohyoid nerve
• Posterior belly of digastric –mastoid notch –facial nerve
• Mylohyoid -mylohyoid line –mylohyoid nerve
• Stylohyoid-styloid process -facial nerve

25. Extrinsic tongue muscles
• Genioglossus
• Hyoglossus
• Styloglossus

26. Lingual nerve
• Branch of posterior division of mandibular nerve
• Lies in infratemporal fossa
• Where chorda tympani joins the nerve
• Comes in direct contact with mandible covered by mucous membrane
,medial to the third molar tooth
• Rests on hyoglossus
• Submandibular ganglion suspends from the lower border with two roots
• Winds around the lower border of the submandibular duct
• Sensory nerve supply to the pre-sulcal part of the tongue

28. Submandibular ganglion
• Small fusiform ganglion
• Part of Parasympathetic system
• Structurally related to lingual
• Functionally connected to facial nerve and Chordatympani
• Consists of parasympathetic and sympathetic roots
• Parasympathetic root – secretomotor pathway to submandibular and
sublingual glands
• Sympathetic root –primary vasomotor supply to the blood vessels
around the glands

30. Thank you