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Front 1

NASAL CAVITY

ROOF
FLOOR

Back 1

3. Roof: composed ofthe cribriform plate anteriorly and body ofthe sphe-
noid posteriorly

4. Floor: formed by the hard palate

Front 2

OLFACTORY NERVE

Back 2

C. Nerves

1. Olfactory nerve: not a single nerve; nerve processes from olfactory neu-
rons aggregate into numerous olfactory nerves which ascend through
the foramina in the cribriform plate and enter the olfactory bulb; the
olfactory tract extends posteriorly from the olfactory bulb

Front 3

ANTERIOR ETHMOIDAL NERVE

Back 3

C. Nerves

2. Anterior ethmoidal nerve: enters the nasal cavity through the cribriform
plate and divides into tlie internal and external nasal nerves; the inter-
nal nasal nerve provides sensory innervation to the anterosuperior parts
of the lateral nasal wall and nasal septum, and the external nasal nerve
exits the nasal cavity between the nasal bone and lateral process ofthe
septal cartilage to supply tlie dorsum and tip ofthe nose

Front 4

MAXILLARY NERVE

-traverses...

Back 4

3. Maxillary nerve

a. Traverses foramen rotundum and emerges into the pterygopalatine
fossa where the pterygopalatine ganglion is suspended from it; its
sensory branches to tlie nasal cavity are noted below

Front 5

MAXILARY NERVE

POSTERIOR SUPERIOR LATERAL NASAL NERVES

Back 5

3. Maxillary nerve

b. Posterior superior lateral nasal nerves: enter the nasal cavity through
the Sphenopalatine foramen, posterior to the middle nasal concha;
supply the posterosuperior part ofthe lateral nasal wall

Front 6

MAXILLARY NERVE

POSTERIOR SUPERIOR MEDIAL NASAL NERVES

Back 6

3. Maxillary nerve

c. Posterior superior medial nasal nerves and their largest branch, the
nasopalatine nerve: enter the nasal cavity through the Sphenopalatine
foramen, posterior to tlie middle nasal concha, and supply the post-
erosuperior, posteroinferior, and anteroinferior parts of the nasal
septum; the nasopalatine nerve continues through the incisive canal
and incisive fossa and provides sensory innervation to the hard pal-
ate posterior to the upper incisors

Front 7

MAXILLARY NERVE

POSTERIOR INFERIOR LATERAL NASAL NERVES

Back 7

3. Maxillary nerve

d. Posterior inferior lateral nasal nerves: arise from the greater palatine
nerve, a branch ofthe maxillary nerve, as it descends in the inferior
part ofthe greater palatine canal; supply the posteroinferior part of
the lateral nasal wall

Front 8

MAXILLARY NERVE

INFRAORBITAL NERVE

Back 8

3. Maxillary nerve

e. Infraorbital nerve: after emerging onto the face through the infra-
orbital foramen, some of its branches supply the anteroinferior part
ofthe lateral nasal wall

Front 9

MAXILLARY NERVE

POSTGANGLIONIC PS...

Back 9

3. Maxillary nerve

t. Postganglionic parasympathetic secretomotor fibers from the pterygo-palatine ganglion course with branches ofthe maxillary nerve ; they
stimulate secretion of nasal glands