It is a short, brief presentation about the para nasal air sinuses.

1. PARANASAL
AIR SINUSES
BY:
SUBHIKSHA.S.R
1st YEAR BDS

2. SYNOPSIS
INTRODUCTION
FEATURES & RELATIONS
FRONTAL AIR SINUS
MAXILLARY AIR SINUS
ETHMOIDAL AIR SINUS
SPHENOIDAL AIR SINUS
CLINICAL SIGNIFICANCE

3. INTRODUCTION
– Paranasal air are air- conditioning cavities in paranasal bones
– Classification : There are 4 air sinuses
Frontal
Maxillary
Ethmoidal
Sphenoidal

4. FEATURES
– They develop as diverticula of respiratory part of nasal cavity into
surrounding bone
– All open into nasal cavity
– Lined by respiratory epithelium
– All supplied by Trigeminal nerve
– Divided into 2 groups: ANTERIOR – open into middle meatus
– POSTERIOR – do not open into middle meatus

5. Relation in relation to THE
ORBIT
– ABOVE : frontal air sinus
– BELOW : maxillary air sinus
– MEDIAL : ethmoidal air
sinus
– BEHIND: sphenoidal air
sinus

7. FRONTAL AIR SINUS
– LOCATION: In the frontal bone deep to superciliary arch ; triangular in
shape.
– OPENING: Hiatus semilunaris of middle meatus through the
fronto-nasal duct.
– They are rudimentary at birth. Well developed in males than females.
– ARTERIAL SUPPLY: Supra orbital artery.
– VENOUS DRAINAGE: Supra orbital and superior ophthalmic veins.
– NERVE SUPPLY: Supra orbital nerve.
– LYMPHATIC DRAINAGE: has Submandibular nodes.

9. MAXILLARY AIR SINUS
• LOCATION: Body of maxilla
• Largest sinus ; pyramidal in shape
• DRAINAGE: Hiatus semilunaris of middle meatus
• ARTERIAL SUPPLY: Posterior superior alveolar artery
Anterior superior alveolar artery
• VENOUS DRAINAGE: Facial vein ,pterygoid venous plexus
• NERVE SUPPLY: Anterior superior alveolar branch
Middle superior alveolar branch
Posterior superior alveolar branch
• LYMPHATIC DRAINAGE: Submandibular nodes

12. ANTERIOR:Anterosuperior alveolar nerves and vessels
POSTERIOR:Posterosuperior alveolar nerves and vessels
SUPERIOR: Infraorbital nerves and vessels
INFERIOR: Premolars and molars and corresponding
nerves and vessels
LATERAL: Middle superior alveolar nerves and vessels
RELATIO
NS

13. • These sinuses are numerous small inter-
connecting spaces within the LABYRINTH
OF ETHMOIDAL BONE.
• LOCATION: Upper part of lateral nasal wall
and orbit.
• They are divided into THREE GROUPS.
— Anterior
— Middle
— Posterior
ETHMOIDAL AIR SINUS

14. ANTERIOR MIDDLE POSTERIOR
No. Of cells 1-11 1-3 1-7
Drainage hiatus semilunaris Bulla ethmoidalis Superior meatus
Blood and nerve
supply
Anterior ethmoidal
nerves and vessels
•Anterior
ethmoidal nerves
& vessels
• orbital br. Of
retro pharyngeal
ganglion
•Posterior
ethmoidal nerves
and vessels
•orbital br. Of retro
pharyngeal
ganglion
Lymph nodes Submandibular Submandibular Retro pharyngeal

15. SPHENOIDAL AIR SINUS
LOCATION: Body of sphenoidal bone and behind the nasal cavity .
OPENING: spheno- ethmoidal recess of nasal cavity
ARTERIAL SUPPLY : posterior ethmoidal and internal carotid artery
VENOUS DRAINAGE: pterygoid venous plexus, cavernous sinus
NERVE SUPPLY:posterior ethmoidal nerve and orbital br. of
pterygopalatine ganglion
LYMPHATIC DRAINAGE: retro pharyngeal nodes

16. SUPERIOR: Pituitary gland,
optic chiasma
INFERIOR: Roof of
nasopharynx
ANTERIOR: Spheno-ethmoidal
recess
POSTERIOR: Pons and medulla
oblongata
LATERAL: Cavernous sinus,
internal carotid artery
RELATIO
NS

17. CLINICAL SIGNIFICANCE
• SINUSITIS- chronic
and acute
• NEOPLASMS CAUSES:
1. Obstruction and sinus
ventilation and drainage
2.Nasal infection
3.Swimming and diving
4.Trauma
5.Dental infection

18. CLINICAL FEATURES:
• Constitutional symptoms
• Headache
• Tenderness
• Oedema of eyelid
• Nasal discharge
• Postnasal discharge
DIAGNOSIS:
1.X-RAY – lateral &
water’s view
2.CT Scan
3.MRI

19. LATERAL VIEW

20. Waters' view is a
radiographic view,
where an X-ray
beam is angled at
37° to
the orbitomeatal
line.[1] The rays
pass from behind
the head and are
perpendicular to
the radiographic
plate. It is
commonly used to
get a better view of
the maxillary
sinuses.

21. Caldwell's view (or Occipitofrontal view) is a radiographic view of skull,
where X-ray plate is perpendicular to the orbitomeatal line. It is
commonly used to get better view of the paranasal and frontal sinuses.

22. Computed tomography (CT) of the sinuses uses special x-ray equipment to evaluate the paranasal sinus
cavities.CT scanning is the most reliable imaging technique for determining if the sinuses are
obstructed and the best imaging modality for sinusitis.

23. TREATMENT
MAXILLARY SINUS is most commonly infected. Hence, it is drained surgically by two ways:
1. ANTRUM PUNCTURE: Breaking the lateral wall of inferior meatus and pushing in fluid and letting it
drain the the natural orifice
2. CALDWELL-LUC OPERATION: Fenestrating the antrum through the canine fossa in the upper vestibule
of mouth