What is the anterior nasal spine?

• A. The floor of the maxillary sinus.
• B. The anterior border of the maxillary sinus.
• C. The junction of the lower part of the nasal septum and the inferior border of the nasal fossa.
• D. The apex of the nasal septum.

Answer: (C)

The anterior nasal spine is a midline bony projection on the maxilla at the base of the nose where the nasal septum attaches to the floor of the nasal cavity. It marks the junction between the lower part of the nasal septum and the inferior border of the nasal fossa (the floor of the nasal cavity). This projection serves as a landmark for the nasal aperture and for cephalometric references. The other descriptions don’t capture this meeting point: the floor of the maxillary sinus or the anterior border of the sinus aren’t at the midline where the septum meets the nasal floor, and the apex of the nasal septum isn’t a defined anterior projection.