The nasal cavity has superior, inferior and lateral walls. The superior
wall is formed by the nasal bones, the nasal part of the frontal bone, the
cribriform plate of the ethmoid bone and the inferior surface of the sphenoid bone. The inferior wall of the nasal cavity is formed by the palatine
processes of the maxillae, connected with the horizontal plates of the palatine bones. The lateral wall has the most complex structure (Fig. 56).
It is formed by the frontal processes of the maxillae and the nasal
surface of its body, the lacrimal bone, the ethmoidal labyrinths, the per-
Fig. 56. Lateral wall of nasal cavity.
1 — cribriform plate; 2 — superior nasal concha; 3 — medial nasal concha; 4 — uncinate
process of ethmoidal bone; 5 — sphenoid sinus; 6 — sphenopalatin foramen; 7 — maxillary
hiatus; 8 — medial plate of pterygoid process; 9 — horisontal plate of palatine bone; 10 —
palatine process of maxilla; 11 — inferior nasal concha; 12 — incisive canal; 13 — anterior
nasal spine; 14 — inferior nasal meatus; 15 — middle nasi meatus; 16 — frontal process of
maxilla; 17 — superior nasi meatus; 18 — nasal bone; 19 — frontal sinus.
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parts by a sagittal septum, although sometimes this septum is absent. The
sphenoidal sinus is connected with the superior nasal meatus.
The anterior, middle and posterior ethmoid air cells are communicated with the nasal cavity.
The bony (hard) palate (palatum osseum) is the bone base of the
upper wall of the oral cavity and the bottom of the nasal cavity. The hard
palate is formed by the palatine processes of the right and left maxillae
and horizontal plates of the palatine bones, joint along the middle line by
the median palatine suture. The alveolar arch of the maxillae limits the
hard palate at the front and sides. In the anterior section of the median
suture there is a foramen called the in с i s i v e c a n a l . The posterior borders of palatine processes are joined with the horizontal plates of the palatine bone by the transverse palatine suture. Behind the lateral section of
this suture, on each horizontal plate, there is an opening of the g r e a t e r
p a l a t i n e c a n a l and two or three foramina of the l e s s e r p a l a t i n e
c a n a l s . These foramina link the oral cavity with the pterygopalatine fossa (Fig. 57). These canals serve as passages for nerves and blood vessels.
Fig. 57. Pterygopalatine fossa, (zygomatic bone partially removed).
1 — sphenopalatine foramen; 2 — pterygoid canal; 3 — greater palatine canal; 4 — pterygopalatine fossa.
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