1. The maxillary sinus is an air-filled space within the body of the maxilla bone that communicates with the nasal cavity. 2. It develops from the 4th month of gestation and reaches its maximum size by 18 years of age. 3. Common pathologies of the maxillary sinus include acute or chronic sinusitis, odontogenic cysts such as dentigerous or radicular cysts, and benign or malignant tumors. 4. Diagnostic evaluation of sinus disease involves medical history, clinical examination including transillumination, and radiographic imaging like panoramic radiograph, CT scan, or MRI.

1. MAXILLARY
SINUS

2. MAXILLARY SINUS
GUIDED BY-
DR. SIMA ODEDRA
PREPARED BY-
DR. HARITA D. PAGHADAL
PG PART I
ORAL AND MAXILLOFACIAL PATHOLOGY
AND MICROBIOLOGY
GDCHA

3. Outline
Introduction
Functions of the paranasal sinuses
Development and anatomy of maxillary sinus
Blood , Nerve supply& Lymphatic drainage of maxillary sinus
Histology of sinuses
Diagnostic evaluation of sinus disease
Associated pathologies
Other Clinical conditions

4. Paranasal sinus are air containing bony spaces which
is lined by respiratory mucosa and communicate
with the nasal airways.
They develop from cranial and facial bones.
There are 4 pairs of paranasal sinuses(bilaterally).
I. Maxillary
II. Frontal
III. Ethmoidal
IV. Sphenoidal
Introduction

6. Functions of paranasal sinuses
1. Warming of inspired air.
2. Humidification of dry air.
3. Lightening of skull weight.
4. Resonance of voice.
5. Filters debris.
6. Accessory olfactory organ.
7. Protects skull from mechanical shock.
8. Production of bactericidal lysozyme

7. Maxillary sinus: development
• Maxillary sinus is the pneumatic space that is lodged inside the body
of maxilla and that communicates with the environment by way of the
middle meatus and nasal vestibule.”
• Also known as “Antrum of Highmore”
• Anatomy of the maxillary sinus was 1st described by Highmore in1651

8. • Maxillary sinus is first of the PNS to develop
• It starts as a shallow groove on the medial surface of maxilla
during the 4th month of intrauterine life.(Koch1930)
• Expansion occurs more rapidly until all the permanent teeth
have erupted. (Bailey 1998, Sadler 1995)
• It reaches to maximum size around 18years of age. (Bailey
1998, Sadler 1995)

10. AGE CHANGES

12. Pyramidal shaped cavity with in the body of
maxilla.
Boundaries:
Apex- zygomatic process of maxilla.
Base- nasal surface of maxilla.
Roof-orbital surface of maxilla.
Floor- alveolar process of maxilla.
Anterior wall- related to infra-orbital plexus of
nerves and vessels and origin of muscles of
upper lip.
Posterior wall - pierced by post. Superior alveolar
nerve and vessels.

13. Anterior Wall Of Maxillary sinus
• Formed by the facial surface of the maxilla.
• Extends from pyriform aperture anteriorly, to ZM suture &
Inferior orbital rim superiorly to alveolar process inferiorly.
• Convexity towards sinus
• Thinnest in canine fossa
Imp structures
• Infraorbital foramen
• ASA, MSA nerves
• Canine fossa

14. Posterior wall of maxillary sinus
• Formed by sphenomaxillary wall.
• A thin plate of bone separate the antral cavity from the infratemporal
fossa. Made of zygomatic and greater wing of sphenoid bone.
• Thick laterally, thin medially.
Imp. structures
• PSA nerve
• Maxillary artery
• Pterygopalatine ganglion
• Nerve of pterygoid canal

15. Floor Of Maxillary Sinus
• Its mainly curved than flat in structure.
• Formed by junction of anterior sinus wall and lateral nasal wall
• Lies 1-1.2 cm below nasal floor
• Close relationship between sinus and teeth facilitate spread of
pathology.

16. Roof Of Maxillary Sinus
• Formed by floor of the orbit and is transverse by the infraorbital nerves. It is flat
and slopes slightly anteriorly and laterally.
Imp. structures
• Infraorbital canal
• Infraorbital foramen
• Infraorbital nerve and vessels.

17. Medial wall of maxillary sinus
• Formed by lateral nasal wall
• Below- inferior , nasal conchae
• Behind- palatine bone
• Above- uncinate process of ethmoid ,lacrimal bone
• Contains double layer of mucous membrane(pars membranacea)
Imp structures
• Sinus ostium
• Hiatus semilunaris
• Ethmoidal bulla
• Uncinate process
• Infundibulum

18. Ostium of maxillary sinus
• Opening of the maxillary sinus is called ostium.
• It opens in middle meatus at the lower part of
the hiatus semilunaris.
• Lies above the level of nasal floor.
• The ostium lies approximately 2/3rds up the
medial wall of the sinus, making drainage of the
sinus inherently difficult.

19. Maxillary sinus : Blood supply
• Branch of third part of maxillary artery (pterygopalatine part)
• Posterior superior alveolar artery
• Infra-orbital artery
• Greater palatine artery.

20. Maxillary Sinus: venous Drainage
• Pterygoid venous plexus
• Sphenopalatine vein and
• Facial vein
 Infection from the maxillary sinus may
spread to involve cavernous sinus via
any of its draining veins as the pterygoid
plexus communicates with the cavernous
sinus by EMISSARY VEIN.

21. Maxillary Sinus : Nerve Supply
• Maxillary division of the trigeminal
nerve,
• i.e. the posterior, middle and anterior
superior alveolar nerves, the infraorbital
nerve and the anterior palatine nerve

22. Maxillary sinus: lymphatic drainage
• Submandibular lymph nodes
• Deep cervical lymph node
• Retro pharyngeal lymph nodes

23. MAXILLARY SINUS :HISTOLOGY

24. • Maxillary sinus is lined by three
layers: epithelial layer, basal
lamina and sub epithelial layer
with periosteum.
• Epithelium is pseudo stratified,
columnar and ciliated.
• As cilia beats, the mucous on
epithelial surface moves from
sinus interior towards nasal
cavity.

25. Diagnostic Evaluation Of Sinus Diseases
• Detailed medical & dental history.
• Clinical examination.
Inspection
Palpation
Percussion
Transillumination
• Radiographs
• CT scan, MRI, Ultrasound
• Endoscopy.

26. INSPECTION :
Middle third of the face should be inspected for the presence
of asymmetry, deformity, swelling, erythema , ecchymosis or
hematoma
EXTRAORAL PALPATION :
Include palpation of the facial wall of the sinus above the
premolar where the bone is thinnest.

27. INTRAORAL EXAMINATION
Examination should be performed for tenderness, or
paresthesia of upper molar and premolar region.
TRANSILLUMINATION TEST:
It is performed in a darkened room by inserting an electrically
safe light into the mouth ( with the lip closed). Good
transilluminate indicates presence of air in the sinus while the
failure of transillumination indicates presence of pus, fluid
, solid lesion or mucosal thickening.

28. palpation
Transillumination test

29. Radiograph
Intra-oral
Periapical
Occlusal
Lateral occlusal

30. Extra-oral
Panoramic
Waters view
Submentovertex
PA view ORTHOPANTOMOGRAM
submentovertex

31. PA SKULL
WATER’S VIEW

32. CT Scan and MRI
CT SCAN

33. MRI SKULL

34. Ultrasound
Introduced by LANDMAN in 1986
Non-invasive
Safe
Quick
Ultrasound waves are generated by
probe.

35. Ultrasound images of maxillary sinus

36. Allows direct visualization in inaccessible areas,such as
maxillary moral roots that are behind distobuccal root of
maxillary 1st molar.
Endoscopy

37. Developmental anomalies & pathologic conditions of
maxillary sinus
Developmental
anomalies
• Agenesis/Aplasia
• hypoplasia
• Supernumerary
sinus

40. Agenesis:
absent of maxillary sinus
Hypoplasia:
Cleft palate, high palate, septal deformity mandibular
dysostosis, malformation of external nose
Supernumerary sinus
two completely separated sinus on same side

41. Maxillary sinusitis
When the inflammation develops in the sinus either due to
infection or allergy it is termed as sinusitis.
Most common disease involving the maxillary sinus.
Maxillary sinusitis can be divided into-
1. Acute - <3weeks.
2. Subacute- 3weeks to 3months.
3. Chronic/Recurrent ->3months.

42. Etiology
1. Infectious causes
a) Bacterial
b) Viral
c) Fungal 2. Non infectious causes
a) Allergic
b) Non allergic
c) Pharmocological
d) Irritants 3. Disruption of mucociliary
drainage
a) Surgery
c) Trauma

43. Clinical features (acute)
Can occur at any age.
Pt. complains of pain, pressure and heaviness at the affected
side.
Headache is the most common.
Facial erythema, swelling, fever.
Drainage of foul smelling mucopurulent material into the
nasal cavity and nasopharynx.
Pain is exacerbated on bending position.
Dull pain may be present on premolar and molar region.

45. Clinical features
(chronic)
Repeated attacks.
Pain and tenderness.
Foul unilateral discharge.
Cacosmia i.e. Fetid odor with bad taste in
mouth.

46. TREATMENT-
• Nasal decongestant
E.g. Ephedrine sulphate, phenylephrine, xylometazoline
• Antibiotics
Amoxicillin- 500mg TDS 10-15days
Augmentin – 625 mg BD 7 days
If patient fails to respond to the initial T/t within 72hrs, culture & sensitivity test
should be carriedout.
• Mucolytic agents:
Benzoin compound
Camphor
Methanol in boiling water
• Analgesic

47. Odontogenic cystic lesions
of maxillary sinus
ODONTOGENIC NON-ODONTOGENIC
DENTIGEROUS CYST MUCOUS RETENSION CYST
(ANTRAL RETENSION CYST)
RADICULAR CYST
KERATOCYST

48.  Also known as follicular cyst
 2nd most common cyst
 it usually appear on the impacted maxillary 3rd molar
DENTIGEROUS CYST

49.  Maxillary sinusitis caused by an apical inflammatory lesion (
radicular cyst)
RADICULAR CYST

50. Odontogenic keratocyst
 Odontogenic keratocyst is an
aggressive cystic lesion and a
common type of tooth derived cyst
due to presence of odontogenic
epithelial remnants in different
regions of jaw.
 In majority of cases, it is located in
mandibular posterior region. But it
can also be found in the maxilla
especially in the canine region.

51. Mucous retention cyst (antral retention cyst)
 seen asadome-shaped lesion on the floor of thesinus.
 Associated with sinusitis.
 Result from obstruction of mucous glands.
 It is usually asymptomatic but may sometimes cause some pain and
tenderness in the teeth and face over the sinus.
 In some cases the cyst disappears spontaneously due to rupture as a
result of abrupt pressure changes from sneezing or "blowing"of the
nose.
 Later on, the cyst may reappear after a few days.

52. MUCOUS RETENSTION
CYST

53. Associated benign tumors
Osteoma in the floor of the maxillary
sinus.
Polyps : Thickened and folded
mucosa in chronic sinusitis
Ameloblastoma

54. Associated malignant
tumors
 The location of nasal cavity and PNS makes
them extremely close to vitalorgans.
 Sino-nasal malignancies are rare but
common in African & Asia than America.
 Among the Sino nasal tumors, 60%-70%
are maxillary sinus tumors.

55.  Other malignant tumors :
 Malignant melanoma.
 Lymphoma
 Salivary type neoplasm
 Sarcomas
 Metastatic tumours
 Commonest type of malignancy involving the maxillary sinus is
squamous cell carcinoma about 80%. The second commonest tumor
involving the maxillary sinus is adenoid cystic carcinoma about 10%.

56. Other clinical conditions associated
with maxillary sinus
pneumatization:
A process of growth by bone resorption on
internal wall of sinus & bone deposition on outer surface of
maxilla
Maxillary sinus extended to many processes :
1. outward to zygomatic process.
2. inward , upward to frontal process.
3. downward to alveolar process.
 When it extend downward into alveolar process ; the apices of
the roots may appears protruded into the sinus.

57. Oro-Antral fistula
 Invasion of the maxillary sinus and
establishment of direct communication with
the oral cavity is referred to as an oro-antral
fistula.
 Fistula:
-It is a biological tract that connect an anatomical
cavity with the external surface or other
anatomical cavity.
-It is always lines by stratified squamous
epithelium and the potency of the tract is
preserved until epithelial cells scraped off.

58. Antroliths
 Antroliths are the calcified
masses found in the maxillary
sinus.
 Asymptomatic but if continues to
grow, blood stain nasal discharge
or facial pain is observed

59. Conclusion
Anatomy physiology and histology of maxillary sinus is important because close
anatomic relation of the frontal sinus, anterior ethmoidal sinus and
the maxillary teeth, allowing for easy spread of infection.
Age changes , extractions leads to pneumatization and other clinical conditions
like oro-antral communication
The ostium lies approximately 2/3rds up the medial wall of the sinus, making
drainage of the sinus inherently difficult but making spread of infection easier
Infection from the maxillary sinus may spread to involve cavernous sinus via any
of its draining veins as the pterygoid plexus communicates with the cavernous
sinus by EMISSARY VEIN.
Most of the pathology associated with maxillary sinus either gives signs and
symptoms of sinusitis or and accidental findings