seminar in the maxillary sinus anatomy, histology, ...etc.

1. PRESENTED BY:
Dr. ASAID HEZAM

2. CONTENTS
• INTRODUCTION………………………………………………........…1
• DEFINITION……………………………………………………….…….2
• DEVELOPMENT……………………………………………….……….3
• ANATOMY…………………………………………………………….…4
• VASCULAR SUPPLY……………………………………….……….5
• HISTOLOGY……………………………………………….……………6
• FUNCTION……………………………………………….……………..7
• DISORDER…………………………………………….………………..8

3. INTRODUCTION
• Paranasal sinuses (PNS) are air containing bony spaces around
the nasal cavity.
• These spaces communicates with the nasal airway and forms
the various boundaries of nasal cavity and named for the bones
in which they locates.
• Paranasal sinuses are present in a variety animals (including
most mammals, birds, and crocodile) .

4. INTRODUCTION
• There are 4 pairs of paranasal sinuses (bilaterally) viz
A. Frontal air sinus
B. Ethmoidal air sinus
C. Maxillary air sinus
D. Sphenoidal air sinus

5. DEFINITION
• Maxillary sinus is a part of series of pneumatic cavity,
which are restricted to the skull in human; called the
paranasal sinuses.
• Maxillary sinus is defined as “ the pneumatic space that is
lodged inside the body of the maxilla and that
communicates with the environment by way of the middle
nasal meatus and the nasal vestibule ”.

6. DEFINITION

7. DEVELOPMENT
• Maxillary sinus is the first of the PNS to develop at
approximately the third month of fetal life.
• The process begins by slow development of a mucosal
pouching of the ethmoid infudibulum.
• The sinus cavity continues to develop as a slit like
invagination of the nasal epithelium into the cartilagenous
nasal capsule.
• This stage of development is called the primary
pneumatization process which continues until late in the
fourth fetal month.
• The second phase of development of the maxillary sinus is
called secondary pneumatization.

8. DEVELOPMENT
• This process starts at approximately the fifth mouth of fetal
life, when the shallow primordium of the maxillary sinus
begins to grow into the adjacent growing bone of maxilla.

9. DEVELOPMENT
• This process proceeds slowly, and by birth sinus appears as a
small ovoid groove on the side of maxillary bone close to the
orbit and measures on average 7mm in anteroposterior length,
4mm in length, with an estimated volume of 6 to 8ml.
• By the 4th or 5th month of age, the sinus can be seen
radiographically on anteroposterior views as a triangular area
medial to the infra orbital foramen.
• At 7 years of age, the rapid growth of maxillary sinus resumes
and continuous for the next 4 to 5 years, corresponding to the
eruption of the permanent teeth.

10. DEVELOPMENT
• The final growth spurts of maxillary sinus takes place
between 12 and 14 years of age, when it extends down to
the same level as the nasal floor.
• With completion of eruption of all the maxillary permanent
teeth, expansion of the maxillary sinus fills the growing
maxillary bone to produce adult pyramidal shape of the
sinus. It reach to maximum size around 18 years of age.
• This expansion into alveolar process places the floor of the
sinus approximately 5 to 12 mm below the floor of nose.

11. DEVELOPMENT
 However, in some patients, some degree of expansion or
pneumatization of the sinus continue throughout life.
 In the 4th week I.D.L- dorsal of 1st pharyngeal arch forms
the maxillary process, which extends forward and beneath
the development eye to give rise to the maxilla.

12. DEVELOPMENT
Horizontal shift of the palatal
shelves & fusion with one another.
Nasal septum separates the 2* oral
cavity from two nasal chamber.
Influences further expansion of the
lateral nasal wall & 3 wall begin to
fold.
3 conchae & meatuses arise

13. DEVELOPMENT
In its development maxillary sinus is in shape :
tubular birth
at
ovoid childhood
in
pyramidal adulthood
in

14.  The maxillary sinus has a horizontal pyramidal shape that
consists of a base, an apex, and 4 sides.
 The base comprises the lateral wall of the nasal cavity,
whereas apex is at the junction of the maxillary and
zygomatic bone (root of the zygomatic).
 The wall of sinus (4 sided pyramid) are related to the
surface of maxilla as follow:
I. Anterior wall: to facial surface of maxilla
II. Posterior wall: to infra-temporal surface of maxilla
III.Inferior wall: to alveolar process
IV.Superior wall: floor of orbit.
ANATOMY

15. ROOF OF THE ANTRUM
 Formed by floor of the orbit and is transversed by the
infraorbital is flat and slopes slightly anteriorly and laterally.
 Imp structures :
1. Infraorbital canal
2. Infraorbital foramen
3. Infraorbital nerve and vessels.
ANATOMY

16. FLOOR OF THE SINUS
 Curved than flat in structure.
 Formed by junction of anterior sinus wall and lateral nasal wall
 Lies 1-1.2cm below nasal floor
 Close relationship between sinus and teeth facilitate spread of
pathology.
ANATOMY

17. ANTERIOR WALL
 Formed by the facial surface of the maxilla.
 Extend from pyriform aperture anteriorly to alveolar process
inferiorly.
 Convexity towards sinus
 Thinnest in canine fossa
 Imp structures:
1. Infraorbital foramen
2. ASA, MSA nerves
3. Canine fossa
ANATOMY

18. POSTERIOR WALL
 Formed by sphenomaxillary wall.
 A thin plate of bone separate the antral cavity from the
infratemporal fossa. Mede 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
ANATOMY

19. MEDIAL WALL
 Formed by lateral nasal wall.
 Below-inferior, nasal conchae
 Above-uncinate process of ethmoid, lacrimal bone
 Behind-palatine bone
 Contains double layer of mucous membrane (pars membranacea)
 Imp structures:
1. Sinus ostium
2. Hiatus semilunaris
3. Ethmoidal bulla
4. Uncinate process
5. infundibulum
ANATOMY

20. LATERAL WALL
 Related to zygoma and cheek.
ANATOMY

21. ANATOMY
OSTIUM
 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.

22. • Greater palatine arteries
• Infra-orbital artery
• Facial artery also contribute.
VASCULAR SUPPLY

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

24. • Pterygoid venous plexus (anterior)
• Sphenopalatin (anterior)
• Facial vein contribute to venous drainage of sinus (posterior)
 Infection from maxillary sinus may spread to involve the cavernous sinus
via draining veins facial vein and emissary vein to cause cavernous sinus
thrombosis.
VASCULAR SUPPLY

25. VASCULAR SUPPLY
1. Submandibular lymph nodes
2. Deep cervical lymph node
3. Retro pharyngeal lymph nodes
 Lymphatic drainage is important
because infections and malignant
tumors may spread along the lymphatic
system
 Drain into deep cervical either directly
or via submandibular nodes.

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

27. • 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.
• Serves as accessory olfactory organs.

28. 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.

29.  It is the inflammation of the maxillary sinus mucosa.
 Types: depending upon duration
I. Acute : sudden onset, duration 4week or less.
II. Subacute : duration 4-12week.
III. Chronic : duration 12week.

30.  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)

31.  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 root.
 Patient complained of regurgitation of food through
the nose while eating.

32. 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

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

34. There are two main approaches to
lift the maxillary sinus
Indirect
Direct
(caldwell luc)

35. indirect
direct

36. Crouzon syndrome: (craniofcial dyostosis) there is early synostosis
of the sutures produce hypoplasia of the maxilla and therefore
maxillary sinus together with high arch palate resulting in crowding
of teeth
As shows brachycephaly, hypertelorism and orbital proptosis

37. Treacher collins syndrome: (mandibulofacial dysostosis)
features may include underdeveloped or absence of
zygomatic bone, downward inclination of palpebral fissure
underdeveloped maxillary sinus and mandible malformed external
ears, high arched or cleft palate.

38. Binder syndrome: (maxillaonasal dysplasia)
features include hypoplasia of middle third of face. There is
maxillary sinus hypoplasia, retrognathic maxilla.

39. Silent sinus syndrome:
spontaneous, asymptomatic collapse of the maxillary sinus and
orbital floor associated with negative sinus pressures. It can cause
painless facial asymmetry, diplopia and enophthalmos.
Usually the diagnosis is suspected clinically, and
it can be confirmrd radiologically by characteristic
imaging features that include maxillary sinus outlet
obstruction, sinus opacification, and sinus volume
loss caused by inward retraction of the sinus wall.

40. REFERNCES
• Human anatomy, head & neck anatomy, atlas anatomy.
• Orban's Oral histology & embryology
• Oral anatomy, histology, and embryology. B.K.B. Berkovitz. G.R. Holland. B.J
Moxham. Fourth edition.
• Atlas of oral diseases. Goeorge Laskaris.
• Maxillary sinus and its implication Killey &Kay
• Cate A.R Ten, Oral histology: development, structure, and function.
• Textbook of oral & general anatomy & maxillofacial surgary of 3 Doctors.
• Soames & Cawson's Oral pathology.
• Seminars on maxillary sinus of some doctors.
• Online location . google ..