Which anatomical landmark is defined as the tip of the bony anterior nasal spine in the medial plane?

The correct choice identifies the anatomical landmark known as the anterior nasal spine (ANS). The anterior nasal spine is a prominent bony projection located at the bottom of the nasal cavity, right in the midline of the face. It serves as a critical reference point in cephalometric analysis as it provides a stable landmark for various measurements related to dental and skeletal relationships in orthodontics and craniofacial studies.

Given its central role and distinctive position, the ANS is often used to establish the position of maxillary teeth and assess facial symmetry. Its precise location at the tip of the bony anterior nasal spine makes it an essential landmark in planning orthodontic treatment and analyzing craniofacial structures.

Other landmarks mentioned serve different anatomical purposes and are not located at the same position as the anterior nasal spine. For instance, Point A is a location related to the maxilla, Pogonion refers to the most prominent point of the chin, and Glabella is the area between the eyebrows just above the nose. Each of these landmarks aids in distinct aspects of facial analysis, but in the context of identifying the specific location of the bony anterior nasal spine, the correct answer remains the anterior nasal spine (ANS).