- The anterior parts of the nasal cavities are held open by a skeletal framework (i.e external nose ).
- The external nose is pyramidal in shape , has anterior border called "dorsum" and two lateral sides.
- It´s root lies at the naso-facial suture.
- It´s apex called the tip of the nose.
- The septum below the tip of the nose called "columella".
- The opening of the nose to air is called "nostrils" or "anterior nares" which are openings through which air enters nasal cavities...
- The external nose is composed of two parts:
1- Upper bony part:-
which is composed of :
- Nsal bones which is articulate together in the middle line .
- Nasal process of frontal bone.
- Nasal process of maxillry bone.
2- lower cartilagenous part:-
which is composed of :
- upper lateral cartilage.
- Major alar cartilage(lower lateral cartilage).
- Minor alar cartilage at ala nasi.
N.B: Major alar cartilage is composed of two crura lateral and medial.
The two medial crura form "columella".
*References:-
-Netter anatomy atlas.
-Richard l.darke,wayne vogl& Adam mitchell:Gray´s anatomy for students.
-Mohammed Fareed:Illustrated Otolaryngology.
-Hassan Allam:Manual of Otorhinolaryngology.
-Mansoura E.N.T department:Essentials of Otorhinolaryngology.