The maxillary sinus is the largest of the paranasal sinuses. It is located within the body of the maxilla and has a pyramidal shape. The maxillary sinus develops during fetal development from the maxillary process and reaches its maximum size by age 18. It is important for functions like voice resonance and warming inhaled air. Disease processes like sinusitis, cysts, tumors or dental infections can involve the maxillary sinus. Radiographs are important for evaluating the sinus floor and its relationship to tooth roots. Surgical procedures may be needed to treat conditions like oroantral fistulas or remove foreign bodies from the sinus.

4.  Paranasal Sinuses (PNS) are air containing bony spaces
around the nasal cavity.
 They develop from cranial and facial bones.
 These spaces communicates with the nasal airway and
forms the various boundaries of nasal cavity and named
for the bones in which they locates.
 They are usually lines by respiratory mucous membrane.

5. There are 4 pairs of paranasal sinuses(bilaterally) viz
a. Maxillary air sinus
b. Frontal air sinus,
c. Ethmoidal air sinus,
d. Sphenoidal air sinus

6. “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”
( Ref: Orban’s Oral Histology – 10th Ed.)

7. The maxillary sinus was
first described and
illustrated by Leonardo da
Vinci,
but the earliest
attribution of significance
was given to Nathaniel
Highmore, the British
surgeon and anatomist
who described it in detail
in his 1651 treatise.

8.  Imparts resonance to the voice
 Increases the surface area and lightens the skull
 Moistens and warms inspired air
 Filters the debris from the inspired air
 Mucus production and storage
 Limit extent of facial injury from trauma
 Provides thermal insulation to important tissues
 Serves as accessory olfactory organs.

9.  It is the first of the paranasal sinus to develop.
 It starts as a shallow groove on the medial surface of
maxilla during the 4th month of intrauterine life.
 Expansion occurs more rapidly until all the permanent
teeth have erupted.
 It reaches to maximum size around 18years of age.
(Koch 1930)
(Bailey 1998)
(Sadler 1995)

10.  In the 4th week I.U.L. – dorsal portion of 1st Pharyngeal
arch forms the Maxillary process, which extends forward
and beneath the developing eye to give rise to the maxilla.

11. • Horizontal shift of the Palatal
Shelves & fusion with one
another.
• Nasal Septum separates the 2°
Oral cavity from the two nasal
chambers
• Influences further expansion
of the lateral nasal wall & 3
wall begin to fold
• 3 Conchae & Meatuses arise

12. • Crouzon syndrome : Early synostosis(fusion) of
sutures produces hypoplasia of the maxilla and
therefore the maxillary sinus together with the high
arched palate.
• Treacher Collins syndrome : Associated with grossly
and symmetrically underdeveloped maxillary sinuses
and Malar bones.
• Binder syndrome : Hypoplasia of middle third of the
face with smaller maxillary length and maxillary sinus
hypoplasia.

13. • Maxillary sinus is Largest of the PNS.
• Pyramidal shaped cavity located within the body of the
Maxillary bone
• The base of the pyramid forming the lateral nasal wall and
apex at the root of the zygoma.

14. • Formed by floor of the orbit and is transversed by the infraorbital nerves. It
is flat and slopes slightly anteriorly and laterally.
• Imp structures
1. Infraorbital canal
2. Infraorbital foramen
3. Infraorbital nerve and vessels.

15.  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. • 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
1. Infraorbital foramen
2. ASA, MSA nerves
3. Canine fossa

17.  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.
 Important structures
1. PSA nerve
2. Maxillary artery
3. Pterygopalatine ganglion
4. Nerve of pterygoid canal

18. • 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
I. Sinus ostium
II. Hiatus semilunaris
III.Ethmoidal bulla
IV.Uncinate process
V. Infundibulum

19. Osteum:
Opening of the maxillary sinus is called osteum.
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.

20. Arterial supply-
• Branch of third part of maxillary artery (pterygopalatine part)
1. Posterior superior alveolar artery
2. Infra-orbital artery
3. Greater palatine artery.

21. o Anteriorly : Facial vein
o Posteriorly : Pterygoid venous plexus
Sphenopalatine vein
Watzek et al. 1997

22. 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.

23. Maxillary division of the trigeminal nerve, i.e.
• the posterior, middle and anterior superior alveolar nerves,
• the infraorbital nerve and
• the anterior palatine nerve.
Last 1959

24. Lymph drainage
1. Submandibular lymph
nodes
2. Deep cervical lymph
node
3. Retro pharyngeal
lymph nodes

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

26. 0-3years
• At birth Filled with
deciduous tooth
germs
• Size:7mm x 4mm x
4mm.Vol 6-8ml
(Sperber,1989)
• 20th month-
posterior
development
(Ennis1937)
• 3rd year : ½ Adult
size
• (Ennis 1937)
3-4years
• Increase in
width with
facial growth
• Position: 2nd
deciduous
molars and
crypts of 1st
permanent
molars.
• More prone to
infections
(Sperber 1989)
7-9years
• Size:27mm x
18mmx17mm
• Growth
corresponds to
permanent teeth
eruption
• Canine present
as ridge in
anterior surface
of sinus
• (Ennis 1937)

27. 9-12years
• Antral floor
same level
with nasal
floor
• Portion of
alveolar
process
vacates and
becomes
pneumatised
• It forms
pyramidal
shape
12-15years
• Floor of sinus 5-
12.5 mm below
nasal floor
• Size:32mm x 33mm
x 25mm (Turner
1902)
• Vol 15-20 ml
(Nivert 1930)
• P Sinus floor : 1st
molar 2nd molar 2nd
premolar
oldage
• Resorption of
ridge with
continued sinus
pneumatization
which leaves a
thin layer of
cortical bone
separating the
sinus mucosa
from oral
mucosa

28. INSPECTION
• Middle third of the face should be inspected for the presence of asymmetry,
deformity, swelling, erythema , ecchymosis or hematoma.
EXTRA ORAL EXAMINATION
• Include palpation of the facial wall of the sinus above the premolar , where the
bone is thinnest.
INTRA ORAL 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 transillumination indicates presence of air in the
sinus while the failure of transillumination indicates presence of pus, fluid , solid
lesion or mucosal thickening.

29. • Peri apical
• occlusal
• Lateral occlusal
INTRA ORAL
• OPG
• WATERS VIEW
• SUBMENTO VERTEX VIEW
• PA VIEW
EXTRA ORAL
• CT SCANS
• MRI
OTHERS

30. • Borders of the maxillary sinus appear as a thin, delicate
radiopaque line .
• In the absence of disease it appears continuous, but on close
examination it has small interruptions in its smoothness or density.
• The roots of maxillary molars usually lie in close apposition to the
maxillary sinus and may project into the floor of the sinus,
causing small elevations or prominences.

32. Provides an extensive overview of the sinus floor and its relationship
with the tooth roots.

36.  Ultrasound is becoming the diagnostic tool of choice for more and more physicians
in detecting sinusitis.
 It offers a fast ,reliable and radiation free method for diagnosing sinusitis and has
been used successfully in Finland for around 15 years.
(Landman 1986)
 Ultrasound beam sent out by the sinus ultra is reflected from the posterior wall of
the sinus when the sinus contains fluid and from the anterior wall when sinus
contains air.

37.  It is an optimal method especially for the assessment of foreign bodies (such as
root filling materials and root tips) that have penetrated into the maxillary sinus.
(Kennedy et al. 1985)

38. 1. Inflammatory - Maxillary sinusitis
2. Traumatic - Fractured root
Sinus contusion
Blow out fracture
Zygomatic complex fracture
3. Calcification Antroliths
4. Cyst Radicular cyst
Dentigerous cyst
Mucous retention cyst
5. Tumor Antral Polyps
Squammous cell carcinoma

39. It is the inflammation of the maxillary sinus mucosa.
Types: depending upon duration
a.Acute : sudden onset, duration 4 week or less
b.Subacute : duration 4-12 week
c.Chronic: duration 12 week

40. • The spread of pulpal disease beyond the confines of the dental
supporting tissues into the maxillary sinus was termed Endo – antral
syndrome (EAS) by Selden (1974).
Ericson & Welander (1966)

41. • The sinus is directly involved in tooth extraction due to the
relation of surrounding structures with maxillary sinus and can
lead to an oroantral communication or complicated by
displacement of roots.
• Patient complained of regurgitation of food through the nose
while eating.

42. oroantral
communication:
Escape of fluids
Epistaxis
Escape of air
Enhanced column of air.
Excruciating pain
oroantral fistula:
Pain.
Persistent purulent unilateral nasal
discharge.
Post nasal drip.
Possible sequale of toxememic condition
Popping out of antral polyp
Surgical Management:
Buccal flap advancement procedure
Palatal pedical flap
Ashley’s operation
Caldwell Luc operation
Intra nasal antrostomy

44. • The use of 7–10 mm long implants is a greater concern in the
maxilla than the mandible because the implant failure rate is higher
in the maxilla.
• Therefore, 13 mm is the recommended minimum occlusocervical
bone dimension in the maxilla.

45. Jensen and Terheyden in 2009,

46. Invented by SUMMER IN 1994

47. A root tip of the maxillary
first molar accidentally
pushed into the sinus at
the time of tooth
extraction.
Removal of root tip can
be done through the tooth
socket or through the
canine fossa by Caldwell
luc approach.

48. • 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

50. Polyps:Thickened and folded mucosa in chronic sinusitis
Osteoma in the floor
of the maxillary sinus.
AMELOBLASTOMA

51. SQUAMOUS CELL CARCINOMA

52. The development of asymptomatic spontaneous
enophthalmos and associated
asymptomatic maxillary sinus disease.
The term “silent sinus syndrome,” emphasizing the
asymptomatic preexisting maxillary condition as the
causative agent for the enophthalmos..

54. REFERENCES
• Textbook of oral and maxillofacialsurgery, Neelima malik
• Maxillary sinus and its implication Killey and Kay
• Textbook of Maxillary sinus Mc’gowan
• Orban’s, Oral histology and embryology, 11th edition.
• Cate A.R. Ten, Oral Histology: development, structure, and function. 6th edition.
• The Location of Maxillary Sinus Ostium and Its Clinical Application (L. C. Prasanna •
H. Mamatha) [Indian J Otolaryngol Head Neck Surg October–December 2010)
62(4):335–337]
• Endo-antral Syndrome and various endodontic complication(JOE May 1999 vol 25(5)
389-393
• J Oral Maxillofac Surgery 62:1028-1033, 2004 The Silent Sinus Syndrome:
• Textbook of general anatomy, B.D. Chaurasia
• ORAL RADIOLOGY : WHITE AND PHAROAH