Paranasal sinus are air containing bony spaces around
the nasal cavity.
There are 4 pairs of paranasal sinuses(bilaterally).
V. It is is also called as Antrum of Highmore.
LARGEST paranasal sinus.
The maxillary sinus was first discovered and illustrated
by Leonardo da vinci, but the earliest attribution of
significance was given by NATHANIEL HIGHMORE.
The British surgeon and anatomist who described it in
detail in the year 1651.
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.
Development of sinus
At the birth- Tubular.
At the childhood-Ovoid.
In the adult- Pyramidal.
Pyramidal shaped cavity with in the body of maxilla.
Apex- zygomatic process of maxilla.
Base- nasal surface of maxilla.
Roof-orbital surface of maxilla.
Floor- alveolar process of maxilla.
Anterior wall is related to infra-orbital plexus of
nerves and vessels and origin of muscles of upper lip.
Posterior wall is pierced by post. Superior alveolar
nerve and vessels.
3 layers surround the space of the maxillary sinus.
1. Epithelial layer
2. Basal layer
3. Sub-epithelial layers including periostium.
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.
Diagnostic evaluation of maxillary sinus.
Detailed medical & dental history.
Ultrasound, CT scan, MRI.
Tapping of lateral wall of sinus over prominence of
cheek bone and palpation intra-orally on lateral
surface of maxilla between canine fossa and zygomatic
It is done by placing a bright flash light or fiber optic
light against the mucosa on the palatal or facial surface
of the sinus and observing the transmission of light
through the sinus in the darkroom.
Agenesis.- Complete absent
Aplasia/ hypoplasia- seen with
Cleft palate, choanal atresia, high palate, septal
deformity, mandibular dysostosis, malformation of
Supernumery- two completely separated sinus on
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 - < 3 weeks .
2. Subacute- 3 weeks to 3 months.
3. Chronic/Recurrent -> 3 months.
Clinical features (acute)
Can occur at any age.
Pt. complains of pain, pressure and heavyness at the
Headache is the most common.
Facial erythema, swelling, fever.
Drainage of foul smelling mucopurulant material into
the nasal cavity and nasopharynx.
Pain is exacerbated on bending position.
Dull pain may be present on premolar and molar
Clinical features (chronic)
Pain and tenderness.
Foul unilateral discharge.
Cacosmia i.e. Fetid odour with bad taste in mouth.
1. Amoxicillin- 500 mg TDS 10-15 days
2. Augmentin – 625 mg BD 7 days
3. If patient fails to respond to the initial T/t within
72hrs, culture & sensitivity test should be carried out.
1. Benzoin compound
in boiling water
Analgesic to reduce pain
Dental implications of maxillary
Spread of infection from periapical/PDL space.
Due to over extension of dental materials .
Result of periapical surgery.
Invasion of the maxillary sinus and establishment of
direct communication with the oral cavity is referred
to as an oro-antral 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.
Factors- influencing creation of
Density of alveolar bone and thickness of sinus.
Size if sinus.
Periodontal disease that may erode the sinus floor.
Presence of cyst or tumor.
Sings & Symptoms
Antral floor fracture.
Fracture of alveolar process or tuberosity.
Evidence of air stream passing from nostril.
Change in speech tone and resonance.
Bubbling of blod from the socket or nostril.
Toothache of maxillary sinus origin
In sinusitis, a feeling of constant dull, aching pressur
can be felt on the posterior maxillary teeth.
Similarities between pulpal pain and sinusitis
Similarities Pulpal pain Sinusitis pain
Sensitive to cold present present
Pain on mastication present present
Toothache of maxillary sinus origin
Dissimilarities Pulpal pain Sinusitis pain
Location Single tooth Can not locate
Radiating pain /headache May/may not be present Present
Fever May/may not be present Present
URTI/ Viral infection Absent Present
Pain of changing position Absent Present
Nasal discharge Absent Present
Foul taste, blood, pus
Mucous retention cyst (antral retention cyst) seen as a
dome-shaped lesion on the floor of the sinus.
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
The location of nasal cavity and PNS makes them
extremely close to vital organs.
Sino-nasal malignancies are rare but common in
African & Asia than America.
Among the sino-nasal tumours, 60%-70% are
maxillary sinus tumours.
Commonest type of malignancy involving the
maxillary sinus is squamous cell carcinoma about
80%. The second commonest tumour involving the
maxillary sinus is adenoidcystic carcinoma about
Other types of malignant tumours
of maxillary sinus:
Salivary type neoplasm
Viral infections – EB virus, and Human papilloma virus
Exposure to wood dust – Especially African Mahogany
wood dust causes adenocarcinoma of maxillary sinus.
People working in nickel and chrome industries are more
prone to develop cancer of maxillary sinus.
People working in leather industries are also known to
develop cancer of maxillary sinus.
Iatrogenic causes – Post irradiation.
Use of snuff have also been documented to be the causative