Maxillary Sinus.

1. HISTOLOGY OF
MAXILLARY SINUS
&
CLINICAL
IMPLICATIONS
-Presented by: Numa Sarang.
FYBDS
Rollno.68

2. MAXILLARY SINUS
 The maxillary sinus is 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.
 It is pyramidal and the largest
of air filled paranasal sinus
in maxilla.
 Maxillary Sinus is also called
as Antrum Of Highmore.

3. Microscopic Features Maxillary Sinus
 Epithelial Layer:
Pseudostratified ciliated
columnar epithelium.
 Basal Lamina
 Sub epithelial Layer
including periosteum (lamina
propria): Connective tissue
shows presence of serous and
mucous glands.

4. EPITHELIUM
 The maxillary sinus is lined by a mucosa which is firmly bound to
the underlying periosteum.
 The epithelium is pseudostratified columnar ciliated and is
derived from the olfactory epithelium of the middle nasal
meatus.
 Epithelial of maxillary sinus lining is thinner than that of the nasal
cavity.
 They have nucleus and cytoplasm containing numerous
mitochondria, enzyme containing organelles and basal bodies
 The epithelium consists of the following cells:
1. Basal Cells
2. Non Cilated Columnar Cells
3. Ciliated Columnar Cells
4. Goblet cells

5. BASAL CELLS
 The basal cells provide
attachment of the ciliary
microtubules to the apical
segment of the cell membrane.
 They are found at the bottom
of the epithelium layer.

6. CILIATED COLUMNAR CELLS
 They are the most numerous cellular type in the
maxillary sinus epithelium.
 The cilia are motile and are composed of 9 +1 pairs of
microtubules.
 Because of the mucociliary motile beating function of
the cilia the debris, microorganisms and the mucous
blanket lining the epithelial surface move from the sinus
interior toward the nasal cavity through the ostium
maxillare.
 Cilia mechanically help in mucus clearance along with
entrapped debris from nose and PNS

7. CILIATED COLUMNAR CELLS
 The cilia beat automatically and
are not under nervous control.
 The beating pattern and direction
are genetically programmed.
 All cilia beat together to form a
metchronous wave.
 Ciliary motility is dependent on
ATP driven molecular motors.

8. HISTOLOGY
C= Cilia
E= Epithelium
LP= Lamina Propria
BV= Blood Vessels

9. HISTOLOGY DIAGRAM
Goblet cell
Cilia
Pseudo columnar Ciliated epithelium
Collagen fibers
Fibroblast
Blood Vessels
Periosteum

10. MICROVILLI
 Hair like projections of the actin
filament.
 These are immotile and are
present on the apical surface along
with cilia.
 Length: 1-2mm.
 Functions:
1. Increases the surface area of the
cell.
2. Prevents drying of the surface.

11. Goblet cells
 Maxillary Sinus has the highest density of
Goblet cells.
 Goblet cell is a unicellular gland which is
mucous synthesizing and secreting cell.
 It is flask shaped cell with a short stack
like basal end containing the nucleus and a
swollen apical end containing mucin &
lysozymes which are protective in function.
 It is an apocrine gland, i.e it pours its
secretion through rupture of its apical cell
membrane that gets regenerated.

12. Goblet cells
 Basal segment the cell is occupied by the nucleus, RER
& SER and Golgi apparatus.
 These are involved in the synthesis of the secretory
mucosubstances.
 They secrete glycoproteins which are responsible for
the viscosity and elasticity of the mucus.
 Goblet cells are innervated by parasymapathetic and
sympathetic nervous system.
 The parasympathetic stimulation induces thicker
mucus.
 Sympathetic stimulation leads to more watery mucus
secretion

13. SUPEPITHELIAL LAYER
 The lamina propria of the maxillary sinus lining
is much thinner than that of the nasal mucosa.
 It is fused with the periosteum and consists of:
1. Intercellular substances: Loose collagen bundles
and very few elastic fibers
2. Serous and mucous glands
3. Blood vessels
4. Subepithelial &Myoepithelial glands
5. Nerve fibers (myelinated and nonmyelinated)

14. SUBEPITHELIAL GLANDS
 These are located in the
subepithelial layer of the sinus
and reach the sinus lumen by
excretory ducts piercing the
basal lamina
 The surface of the sinus has a
mixed secretory product:
 Serous secretion: consisting of
water, lipids, proteins,
carbohydrates
 Mucous secretion: consisting of
compound glycoproteins or
mucopolysaccharides

15. SUBEPITHELIAL GLANDS
 The acini of subepithelial glands contain in
varying proportions two types of secretory cells:
1. Serous
2. Mucous.
 The serous cell shows an electron-dense,
homogeneous secretory material.
 The mucous cell shows an electron-lucent,
heterogeneous secretory material on staining.
 The serous secretions are watery and thin
whereas the mucous secretions are thick and rich
in mucopolysaccharides
 The myoepithelial cells surround the acini
composed of either serous or mucous type or
both and they help in contraction.

16. SUPEPITHELIAL LAYER
 The secretion from these glands & other exocrine
glands is controlled by the ANS.
 The autonomic axons and general sensory components
are supplied to the maxillary sinus from the maxillary
nerve complex.
 Numerous nonmyelinated and fewer myelinated
axons are observable in the subepithelial layer of the
sinus.
 Blood capillaries, fibroblasts, fibrocytes, collagen
bundles, and other connective tissue elements are also
observed in this layer.

17. CLINICAL IMPLICATIONS
ORONASAL/OROANTRAL FISTULA:
 The upper first molar tooth is most closest to the floor of the
maxillary sinus, surgical manipulation on this tooth may break
through the partitioning bony lamina and thus establish an
oroantral fistula.
 In this situation, oronasal cavity communication can develop
and infection can spread to the nasal as well as the oral cavity.
 Maxillary Sinus is more developed in females hence greater
possibility of oroantral fistulas are seen.
 CAUSES:
1. Removing floor of sinus during extraction
2. Radicular cyts, granuloma or abscess
3. Broken root forced into the sinus if bone is thin
4. Hypercementosis of root apices and its extraction

18. TREATMENT:
•Repair can be done by using local or free soft tissue flaps.
•Untreated fistulas can epithelialize and permanently connect
the maxillary space and oral cavity.
•Radiographs should be considered prior to surgical
intervention.

19. DENTAL INFECTIONS
 The palatal roots of the Maxillary
Second molar followed by 1st
molar, 3rd molar, 2nd premolar and
the canine are most close to the
sinus.
 Infections from maxillary
premolars and molars can easily
communicate and infect maxillary
antrum.

20. MUCOPERIOSTEAL INFECTIONS
 Chronic infections of the mucoperiosteal layer of the
sinus may involve superior alveolar nerves.
 These nerves are closely related to the sinus and can
cause neuralgia
 Diagnosis:
 Inspection of all the upper teeth and the walls of
maxillary sinus since the nerves are coursing through
them
 Infraorbital nerve: roof
 Anterosuperior alveolar nerve: anterior wall
 Middle superior alveolar nerve: lateral aspect
 Posterosuperior alveolar nerve : posterior wall
 Greater and lesser palatine nerves: posteromedial
aspect run very closely.

21. TIC DOULOUREUX
 Tic douloureux is neuralgia of
maxillary nerve (trigeminal)
and may mimic sinus pain.
 Because of overlap of nerves
and close topographic
relationships between the teeth
and the sinus the cause of pain
is often difficult to assess.

22. SINUSITIS
 During bacterial sinusitis or
infections caused by the
streptococci, staphylococci,
pneumococci or the virus of the
common cold, sinus lining becomes
thick and inflammed this compresses
the alveolar nerve supply of the
maxillary posterior teeth and cause
tenderness of the maxillary teeth.
 Symptoms:
1. Nasal congestion
2. Facial pain
3. Chronic Tooth ache
4. Sinus Pressure
5. Runny nose

23. DEVELOPMENTAL ANOMALIES
1. Agenesia: Complete absence of maxillary sinus
2. Aplasia: Altered development
3. Hypoplasia: Underdevelopment
4. Hyperplasia: Excess development eg. Acromegaly
Hypoplasia
Normal

24. DEVELOPMENTAL ANOMALIES
 Supernumerary Sinus:
Occurrence of 2 completely
separated sinuses on the same
side.
 Pituitary Gigantism:
Sinuses larger than normal
 Congenital infection:
Sinuses smaller than normal
eg. Spirochetes in Congenital
syphilis
Large Sinus seen in PNS view

25. MALIGANT LESIONS
1. Adenocarcinoma
2. Squamous Cell Carcinoma
3. Osteosarcoma
4. Fibrosarcoma
5. Lymphosarcoma
Primary manifestation in
maxillary teeth can cause:
1. Pain
2. Loosening of teeth
3. Supraeruption
4. Bleeding in gingival tissue