6. PARANASAL SINUSES
Arranged in pairs
Except ethmoidal sinuses-3 groups of air-filled
spaces
All of them open into the nasal cavity through its
lateral wall
Lined by mucous membrane consisting of
ciliated columnar epithelium
7. PARANASAL SINUSES
Pneumatic diverticula from the nasal cavity
Process begins prenatally
Continues through the course of an organism's lifetime
At birth→ rudimentary/ absent. Enlarge rapidly →6-7
years. (during time of eruption of permanent tooth and
then after puberty)
Birth to adult life, the growth→ resorption of the
surrounding cancellous bone
8. MAXILLARY SINUS
Also k/a ANTRUM OF HIGHMORE.
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
11. MAXILLARY SINUS
Horizontal shift of palatal shelves
Fusion of the 2 shelves with one
another
Fusion with the nasal septum
Nasal septum separate the secondary
oral cavity from 2 secondary nasal
chambers
Folding of lateral nasal wall→ 3 nasal
conchae & 3 nasal meatus
13. MAXILLARY SINUS
Established in the embryo of about 32
mm CRL
Expands vertically into the primordium of
the maxillary body
Diameter -1mm in 50mm CRL fetus
3.5mm in 160mm CRL fetus
7.5 mm in 250 mm CRL fetus
17. MAXILLARY SINUS
Roof → floor of the orbit
Floor→ alveolar process of the maxilla, very
small
Base→ nasal surface of body of maxilla
Apex→ extends into the zygomatic process of
the maxilla
Anterior wall→ infraorbital plexus of nerves
canalis sinuosus.
Posterior wall →anterior boundary of
infratemporal fossa
18. MAXILLARY SINUS
Opens into
middle meatus of
the nose in the
lower part of the
hiatus
semilunaris
Second opening
is often present
at the posterior
part of the hiatus
21. MAXILLARY SINUS
Septa in the
maxillary sinus give
a compartmentalized
appearance to the
sinus
22. MAXILLARY SINUS
Pneumatization of the sinus:
is the enlargement of a sinus by resorption of alveolar bone that
formerly served to support a missing tooth or teeth and then
occupies the edentulous space.
A thin cortex remains over the alveolar ridge (arrow) to maintain
a normal contour. Maxillary sinus showing septa that divide it into
separate compartments
23. MAXILLARY SINUS
Arterial supply Anterior superior alveolar artery
Middle superior alveolar artery
Posterior superior alveolar artery
Venous drainage Facial vein
Pterygoid plexus of veins
Lymphatic
drainage
Submandibular lymph nodes
Nerve Supply Anterior superior alveolar nerve
Middle superior alveolar nerve
Posterior superior alveolar nerve
Branches of maxillary nerve
Branches of infra-orbital nerve
26. HISTOLOGY:
3 microscopically distinct layers surround the
space of the maxillary sinus:
Epithelial layer
Basal lamina
Sub epithelial layer- including the periosteum
27. HISTOLOGY
. It is lined by pseudo stratified ciliated
columnar epithelium.
.
The epithelial layer is mainly composed of
ciliated columnar cells. Along with these,
there are non ciliated columnar cells, basal
cells and goblet cells.
29. GOBLET CELL
Goblet cells are unicellular secretary organ
which are goblet shaped with a basally
placed nucleus and apical cytoplasm filled
with secretory products, producing mucous.
In a hematoxylyn and eosin stained section
cytoplasm of goblet cells appear empty. Cilia
of the lining epithelium help to move the
secretions.
30. HISTOLOGY
This epithelium is separated from sub
epithelial connective tissue by a basal
lamina.
Sub epithelial connective tissue layer has
collagen fibers and fibroblasts and also minor
salivary glands which include both serous
and mucous glands. This layer is attached to
the periosteum of the bone of the maxilla.
31. MAXILLARY SINUS
Important Histologic features:
1. Pseudo stratified ciliated columnar
epithelium
2. Goblet cells
3. Both serous & mucous minor salivary
glands
33. MAXILLARY SINUS
Accessory space to nasal cavity
Humidifying & heating of inhaled air
Protects internal structures like brain, &
eyeball against exposure to cold air
Resonance of voice
Lightening of skull weight
Resistance to mechanical shock
38. MAXILLARY SINUS
Aplasia/ hypoplasia:
altered/ under development –alone or in
association with other anomalies like-
cleft palate, high palate, septal deformity,
absence of concha, mandibulofacial
dysostosis
39. CLINICAL CONSIDERATION
Maxillary sinusitis
Inflammation of the sinus
lining - Sinusitis
Commonly caused
by bacterial, viral, & / or
microbial infections; as
well as, structural
issues such as blockage
of the sinus opening
(ostium).
If the ostium becomes
swollen normal mucus
drainage may not occur.
Which may lead to
infection & inflammation
of the sinuses
40. It causes headache with thick purulent
persistent discharge from nose
Diagnosed by:- transillumination &
radiograph
In chronic cases:- superior alveolar nerve
is involoved & may cause pain.
(Examination of maxillary sinus &
maxillary teeth is required—due to
pathology)
41. RELATIONSHIP OF MAXILLARY SINUS &
MAXILLARY MOLAR
The roots of the
maxillary first and
second molars are in
intimate relation to the
floor of the maxillary
sinus .
42. MAXILLARY SINUS
Infections:
Sinusitis:
an inflammation of the paranasal sinuses, which may or may not
be as a result of infection from bacterial, fungal, viral, allergic or
autoimmune issues
-(Wikipedia, the free encyclopedia)
Rhinosinusitis:
Newer classifications of sinusitis refer to it as rhinosinusitis
Taking into account the thought that inflammation of the
sinuses cannot occur without some inflammation of the nose as
well (rhinitis)
(-Ramadan H, Sanclement J, Thomas J (2005). “Chronic rhinosinusitis and
biofilms.". Otolaryngol Head Neck Surg 132 (3): 414–7)
44. MAXILLARY SINUS
Sinusitis:
Classification:
A. By location:
Maxillary sinusitis - pain or pressure in the maxillary
area
Frontal sinusitis - pain or pressure in the frontal sinus
cavity
Ethmoid sinusitis - pain or pressure pain
between/behind eyes
Sphenoid sinusitis - pain or pressure behind the eyes,
but often refers to the vertex of the head
45. MAXILLARY SINUS
Sinusitis:
Classification:
B. By duration:
Acute: going on less than four weeks
Subacute: between 4-12 weeks
Chronic: going on for 12 weeks or more
(-Harrison's Manual of Medicine 16/e)
46. MAXILLARY SINUS
Acute Sinusitis:
Precipitated by an earlier URT infection→ viral
Most common: Haemophilus influenzae, Streptococcus
pneumoniae, Moraxella catarrhalis, Staphylococcus
aureus
Others: dental problems, fungal invasion, diabetes or
other immune deficiencies
Blocking of openings to the sinuses, allergies
Maxillary sinusitis caused by apical
infection and extensive periodontal
lesions involving the molars and
premolar
47. MAXILLARY SINUS
Symptoms :
Pain, tenderness, and swelling
Yellow or green pus
Fever & chills
Change in vision or swelling around the eye→
very serious condition
48. CONTD……
Histologic feautures:
Acute inflammatory infiltrate with edema of
the connective tissue
Squamous metaplasia of the specialized
ciliated columnar epithelium
49. MAXILLARY SINUS
Acute Sinusitis:
Diagnosis :
Typical symptoms
Radiographic studies
Computed tomography (CT)
Check for dental abscesses
Endoscopic view
Left-sided maxillar sinusitis
(Absence of the air transparency
of left maxillar sinus)
50. MAXILLARY SINUS
Management:
Antihistamine along with decongestant or pain
reliever
Antibiotics
Rest
Nasal irrigation/sparys
Hot drinks
Most cases of acute sinusitis, antibiotics and
nasal corticosteriods work no better than a
placebo”
Pulsating nasal irrigator
(Ian G. Williamson et al. "Antibiotics and Topical Nasal Steroid for
Treatment of Acute Maxillary Sinusitis". JAMA 2007; 298: 2487–249)
51. MAXILLARY SINUS
Chronic Sinusitis:
Multifactorial→ allergy, environmental factors such as
dust or pollution, bacterial infection, or fungus (either
allergic, infective, or reactive)
Non allergic factors→ Vasomotor rhinitis can also cause
chronic sinus problems
Abnormally narrow sinus passages,
Streptococcus bacteroides,veillonella species
54. MAXILLARY SINUS
Fungal Sinus Infections:
Fungi can cause significant nasal and sinus
inflammation
“Triggers” & incite an inflammatory response in
susceptible individuals
Fungus balls are an overgrowth of fungi in
otherwise healthy people
Symptoms: sinus pain, pressure, nasal
congestion, drainage of fluids, chronic infections
56. MAXILLARY SINUS
Fungal Sinus Infections:
Allergic fungal sinusitis:
Fungi cause a reaction characterized by marked
nasal congestion and the formation of nasal and
sinus polyps
Polyps obstruct the nose and the openings to
the sinuses and produce chronic inflammation
Involve only one side of the nose
Management: Surgery/corticosteroids/
antibiotics/ antifungal drugs
57. MAXILLARY SINUS
Fungal Sinus Infections:
Invasive fungal sinusitis:
Very serious disorder
In those immune system is impaired by
chemotherapy or by diseases such as poorly
controlled diabetes, leukemia, lymphoma, multiple
myeloma, or AIDS
Symptoms: pain, fever, and discharge of pus from
the nose
The fungus may spread to the eye socket, causing a
bulging of the affected eye (proptosis) and blindness
Management: Biopsy, surgery, antifungal drugs
62. MAXILLARY SINUS
Antrolith:
•Antroliths are calcified
masses found in the
maxillary sinus
•They are formed by
deposition of calcific material
on a nidus such as a root
fragment, bone chip, foreign
object, or a mass of stagnant
mucus in sites of previous
inflammation
63. MAXILLARY SINUS
Foreign bodies:
needs to be made to differentiate between clearly
demarcated real images, and blurred magnified ghost
images of foreign bodies
64. MAXILLARY SINUS
Oro-antral fistula:
following dental extraction are only noticeable on
panoramic radiography when large and within the
panoramic image layer
66. MAXILLARY SINUS
The growth of tumors within the maxilla is not
concentric
Hence, the site of origin is not necessarily the
epicenter of the lesion
The early detection of insidious maxillary sinus
disease can be very important for the patient’
prognosis, especially in the case of malignant
neoplasia