Maxillary Air Sinus: Size, Shape, and Anatomical Landmarks

Maxillary Air Sinus: Size, Shape, and Anatomical Landmarks

Describe Maxillary Air Sinus & its relations
Answer:

Maxillary Sinus:

• It is largest of all sinuses
• It lies in the body of maxilla

Maxillary Air Sinus Size:

• Height-3.5 cm
• Width-2.5 cm
• Anteroposterior depth- 3.5 cm

Maxillary Air Sinus Boundaries:

• It is pyramidal in shape
• Base-directed medially towards lateral wall of the nose
• Apex-Directed laterally in the zygomatic process of the maxilla
• Roof- formed by Floor of the orbit
• Floor- Formed by alveolar process of maxilla

Maxillary Air Sinus Opening:

• It opens into middle meatus of nose in the lower part of the hiatus semilunaris
• A second opening is present at the posterior end of hiatus
• This opening is reduced in intact skull as it is overlapped by the following.

1. 1. Uncinate process of the ethamoid- from above
   2. Ethamoidal process of inferior nasal concha- from below
   3. Perpendicular plate of palatine bone- from behind
   4. Descending process of the lacrimal bone- from front

Maxillary Air Sinus Relations:

Maxillary Air Sinus Blood Supply:

Arterial Supply:

• Facial artery
• Infraorbital artery
• Greater palatine artery

Maxillary Air Sinus Venous Drainage:

• Facial vein
• Pterygoid plexus of veins

Maxillary Air Sinus Nerve Supply:

• Infraorbital nerve
• Anterior, middle & posterior superior alveolar nerve

Maxillary Air Sinus Lymphatic Drainage:

• Into Submandibular lymph nodes