Nose: Maxillary Sinus

Question 1

Site

Answer 1

1. Largest
2. Only one present at birth
3. Pyramidal
4. Occupies whole maxilla body

Question 2

Relations

Answer 2

1. Apex
2. Base
3. Roof
4. Floor
5. Anterior wall
6. Posterior wall

Question 3

Apex

Answer 3

Towards zygomatic bone (lateral)

Question 4

Base

Answer 4

Towards nasal cavity (medial)

Question 5

Roof

Answer 5

Floor of orbit (infra-orbital groove and canal) containing Infraorbital nerve and vessels

Question 6

Floor

Answer 6

1. Alveolar process of maxilla (1cm below nose floor, opposite 2nd premolar and 1st molar)
2. Damage of floor during these teeth extraction leads to oroantral fistula

Question 7

Anterior wall

Answer 7

Subcutaneous containing anterior superior nerve and vessels

Question 8

Posterior wall

Answer 8

1. Separates sinus from Pterygopalatine fossa
2. Pierced by posterior superior alveolar nerve and vessels

Question 9

Opening

Answer 9

1. Large and rounded (2 cm)
2. In upper part of base
3. It opens in middle meatus at posterior end of hiatus semilunaris (accessory small openings are usually present behind main opening)
4. Its higher position makes drainage of any collection of pus or blood very hard

Question 10

Vessels and nerves related

Answer 10

1. In roof (Infraorbital groove and canal)
2. In anterior wall
3. In lateral wall
4. In posterior wall
5. Behind sinus

Question 11

In roof

Answer 11

Infraorbital nerve and vessels

Question 12

In anterior wall

Answer 12

Anterior superior alveolar (Infraorbital nerve and vessels)

Question 13

In lateral wall

Answer 13

Middle superior alveolar (Infraorbital nerve and vessels)

Question 14

In posterior wall

Answer 14

Posterior superior alveolar (maxillary nerve and vessels)

Question 15

Behind sinus

Answer 15

Greater palatine
(Maxillary nerve and vessels)
Supply posterior wall