Dr. lama khaled El Banna Faculty of Oral and Dental Medicine Al – Azhar University

1. Oral cavity and pharynx
Ehab ZAYYAN, MD

2. The mouth (oral cavity)
• Boundaries: vermillion border of the lips to
junction of hard and soft palate superiorly
and linea terminalis inferiorly.
• Vestibule: between the lips and cheeks
externally and the gums and teeth
internally
• Mouth cavity proper: within the alveolar
arches.

3. Components of the oral cavity
• Lip
• Cheeks
• Upper and lower alveolar ridges
• Retromolar trigone
• Oral tongue (anterior 2/3)
• Hard palate
• Floor of mouth

6. • Opposite to the upper 2nd
molar tooth id the
opening of the parotid gland duct (Stensen
duct).
• In the midline of the floor of the mouth is
the lingual frenulum.
• On each side of the frenulum is a small
papilla. On it lies the orifice of the
submandibular gland duct (Wharton duct)
• Sublingual fold: the bulge of the
sublingual gland.

9. Teeth
Deciduous teeth:
• 20 in number: 4 incisors, 2 canines, 4
molars in each jaw
• They begin to erupt at 6 months and
complete at the end of the second year of
life.

10. Permanent teeth:
• 32 in number
• 4 incisors, 2 canines, 4 premolars and 6
molars in each jaw.
• They begin to erupt at the 6th
year.
• The 2nd
molar erupts at 12th
year of age,
while the 3rd
molar (wisdom teeth) erupts
between 17th
and 30th
years.

13. Tongue
• The tongue is a mass of striated muscle
covered by mucous membrane.
• Its anterior 2/3 lies in the mouth while its
posterior 1/3 lies in the oropharynx.
• The tongue is attached by muscles to the
styloid process, soft palate, mandible and
hyoid bone.
• Divided into right and left halves by a
median fibrous septum.

14. Mucous membrane of the tongue
• Sulcus terminalis: v- shaped sulcus that
divides the tongue into anterior (oral) and
posterior (pharyngeal) parts
• Posterior part = root of the tongue = tongue
base = lingual tonsil
• Foramen cecum…
• Papillae: found on the surface of the anterior
tongue only. They are 3 types:
1. Filiform papillae
2. Fungiform papillae
3. Vallate papillae

17. • The root of the tongue is covered with
irregular lymphoid tissue called the
lingual tonsil.
• Frenulum of tongue
• Deep lingual veins
• Valleculae: pockets created by the
glosso-epiglottic folds between the base
of the tongue and the epiglottis.

20. Muscles of the tongue
• Intrinsic muscles
• Extrinsic muscles

25. Sensory innervation of the tongue
Anterior 2/3:
• Lingual nerve
(branch of the
trigeminal nerve)
gives normal
sensation (touch,
pain, temperature)
• Chorda tympani
nerve (branch of
the facial nerve)
gives taste
sensation.

26. Posterior 1/3 (base):
The glossopharyngeal
nerve gives both
normal and tast
sensation.
The most posterior and
the valleculae: by the
vagus nerve.

28. The pharynx
• The pharynx is
located behind the
nasal cavities, the
mouth and the larynx
• From the skull base
till the C6
• It is a musculu-
membranous wall that
is deficient anteriorly.

30. Pharynx- posterior view

31. Muscles of the pharynx
• Constrictor muscles (superior, middle,
inferior)
• Stylopharyngeus muscle
• Salpyngopharyngeus muscle
• Palatopharyngeus muscle
• The lowest fibers of the inferior constrictor
muscle is called the cricopharyngeus
muscle which act as a phincter.

32. pharyngeal constrictor muscles

34. Nasopharynx
• The pharyngeal tonsil
(adenoid): a collection of
lymphoid tissue in the
submucosa of this region
• Lateral walls: pharyngeal
opening of the auditory
tube. The posterior margin
of the tube forms an
elevation called tubal
elevation (torus
tubarius).

35. • The pharyngeal recess: a small depression in the
lateral wall behind the torus tubarius.
• Tubal tonsils: a collection of lymphoid tissue in the
submucosa behind the opening of the auditory tube.

36. Oropharynx
• From the soft palate to the
upper border of the epiglottis
• Roof: undersurface of the
soft palate. Small collections
of lymphoid tissue are
present in the submucosa of
this area.
• Floor: root of the tongue and
the valleculae.
• Anterior wall: oropharyngeal
isthmus
• Posterior wall: C2, C3

37. • Lateral wall: palatoglossal and
palatopharyngeal arches and the
palatinal tonsils
• Palatoglossal arch: mucosal fold
covering the palatoglossus muscle.
• Palatopharyngeus arch: the mucosal
fold ceovering the palatopharyngeus
muscle

40. •

41. Palatine tonsils
• Two masses of lymphoid tissue
located in the tonsillar fossa.
• The tonsil is covered by
mucous membrane and its
medial surface is free projecting
in the cavity of the pharynx
• Tonsillar crypts on the
surface.
• Fibrous capsule covers the
lateral surface of the tonsil. It
separates it from the superior
constrictor pharyngeal muscle.

43. • The internal carotid artery lies 2.5 cm
behind and lateral to the tonsil.
Blood supply of the tonsils:
• Mainly by the tonsillar artery, a branch of
the facial artery.
• Lymphatic drainage: jugulo-digastric
lymph nodes

44. Waldeyere’s ring of lymphoid tissue
• At the junction of the
mouth and
oropharynx and the
nose with the
nasopharynx there is
a collection of
lymphoid tissue:
1. Palatine tonsils
2. Lingual tonsils
3. Pharyngeal tonsils
4. Tubal tonsils

45. Hypopharynx (laryngopharynx)
• From the upper border of the epiglottis till
the lower border of the cricoid cartilage.
• Anterior wall: inlet of the larynx and the
mucous membrane covering the posterior
surface of the larynx.
• Posterior wall: C3 – C6 vertebrae
• Lateral wall: supported by the thyroid
cartilage & thyrohyoid membrane.

48. Nerve supply of the pharynx
• Pharyngeal plexus: glossopharyngeal,
vagus and sympathetic nerves
• Motor nerve supply: cranial accessory
nerve via branches of the vagus nerve
supplies all the muscles of the pharynx
except the stylopharyngeus which is
supplied by the glossopharyngeal nerve

49. Sensory nerve supply:
• Nasopharynx: maxillary nerve
• Oropharynx: glossopharyngeal nerve
• Hypopharynx: internal laryngeal branch of
the vagus