Oral cavity. Gross anatomy and histology
of the tongue and salivary glands.
Sándor Katz M.D.,Ph.D.
Oral cavity
Boundaries:
• Anterior wall: lips
• Superior wall: hard and soft palates
• Inferior wall: mylohyoid muscle
• Lateral wall: cheeks (buccinator muscles)
Parts:
• vestibule• oral cavity proper• isthmus of fauces
Vestibule and oral cavity proper
hard palate
soft palate
Isthmus of fauces
palatine tonsil
Isthmus of fauces
Tongue
1: dorsum
4: apex
2: root
3: body
Tongue
Foramen cecum: Developmental remnant of the thyroglossal duct (for the descensus of the thyroid gland).
Tongue
Tongue
epiglottic valleculae
Tongue - muscles (visceral striated)
Tongue - muscles
Tongue - muscles
Tongue - muscles
hyoglossus
styloglossus
Tongue - muscles
Tongue - muscles
Tongue - muscles
Tongue - muscles
Tongue - motor innervation
Tongue - sensory innervation
General sensation:• Anterior two-thirds: lingual
nerve• Posterior one-third:
glossopharyngeal nerve
Taste sensation:• Anterior two-thirds: chorda
tympani (from facial nerve)• Posterior one-third:
glossopharyngeal nerve
Tongue - blood supply
Lingual artery:• Deep lingual
artery• Sublingual
artery
Lingual vein deep lingual veinretromandibular veininternal jugular vein
Pirogov’s triangle(perfect place to ligate the lingual artery)
Boundaries:
• posterior edge of mylohyoid
• posterior belly of digastric
• hypoglossal nerve
Content: lingual artery
Histology of the tongue
Covering epithelium:
• stratified non-keratinized squamous epithelium
Papillae:
• filiform• fungiform• foliate• circumvallate
Histology of the tongue
Filiform papillae:
• conical, elongated projections
• covered by the highly keratinized stratified epithelium
• do not reprsent taste buds
• they have mechanical role
Histology of the tongue
Fungiform papillae:
• mushroom-shaped projections
• taste buds are presented in the stratified squamous epithelium on the dorsal surface of papillae
Histology of the tongue
Foliate papillae:
• consist of parallel low ridges separated by deep mucosal clefts
• taste buds are presented on the lateral sides
• small serous glands empty into the the clefts
Histology of the tongue
Circumvallate papillae:
• 8 to 12 papillae locate in front of the terminal sulcus
• taste buds are presented on the lateral sides
• each papilla surrounded by a moatlike invagination lined with stratified squamous epithelium
• von Ebner’s glands empty their serous secretion into the base of the moatlike invaginations
Histology of the tongue
• glands• striated visceral
muscle fibers• stratified non-
keratinized squamous epithelium
Taste buds
Sensory cells:• the most numerous cells• they show microvilli• at their base they form a synapse with the
processes of afferent sensory neurons• turnover time is about 10 days
Supporting cells: • they represent microvilli and tight junctions• turnover time is about 10 days
Basal cells: • small cells located in the basal portion, near
to the basal lamina• they are the stem cells for the two other cell
types
Salivary glands
Major salivary glands:
• Parotid
• Submandibular
• Sublingual
Minor salivary glands:They are 800-1000 glands located throughout the oral cavity within the submucosa.
Submandibular gland
• located in the submandibular trigone
• the facial artery is embedded to its medial/internal side
• the facial vein attaches to its external side
• the lingual nerve is presented at its superior side
• it is supplied by the lingual artery and innervated by the submandibular ganglion via lingual nerve
Submandibular gland
• the submandibular duct arises from its medial side and enters to the lateral lingual groove
Submandibular gland
• the submandibular ducts open onto the surface of the sublingual caruncles on either side of the lingual frenulum
Submandibular gland - lateral lingual sulcus
• V-shaped groove
• medial wall: hyoglossus
• lateral wall: mylohyoid
• contents from superior to inferior: lingual nerve, submandibular duct, hypoglossal nerve
Submandibular gland - histology
• mixed gland
• mostly serous acini
• Gianuzzi’s demilunes
Submandibular gland - histology
intercalatedduct
striated duct
Submandibular gland - histology
interlobular duct
Sublingual gland
• located on the upper side of the mylohyoid anterior to the submandibular gland
• their multiple small ducts empty into the submandibular duct as well as directly onto the floor of the mouth
• it is supplied by the sublingual artery and innervated by the submandibular ganglion via lingual nerve
Sublingual gland
• located on the upper side of the mylohyoid anterior to the submandibular gland
• their multiple small ducts empty into the submandibular gland as well as directly onto the floor of the mouth
• it is supplied by the sublingual artery and innervated by the submandibular ganglion via lingual nerve
Sublingual gland - histology
• mixed gland
• mostly mucous acini
• Gianuzzi’s demilunes
Parotid gland
• it is located in the parotid nest
• covered by the parotid fascia
• parotid duct travels underneath the zygomatic arch and at the anterior edge of the masseter turns to medial and pierces the buccinator than enters to the vestibule of the oral cavity at the level of second molar tooth
Parotid gland
• supplied by the external carotid artery and drained by the external jugular vein
• the facial and auriculotemporal nerves run through the gland
• the auriculotemporal nerve provides secretomotor (parasymathetic) innervation for it
Parotid gland - histology
• completely serous gland
Thank you for your attention.
References: Drake: Gray’s Anatomy for Students, 2nd ed.Standring: Gray’s Anatomy, 39th ed.Radiopaedia.orgThieme Atlas of Anatomy, Head and Neuroanatomy, 2nd ed.
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