# Which of the following is a derived cephalometric landmark? A. Nasion  B. ANS C. Gnathion D. Orbitale The correct answer is C. Gnathion Anatomic landmarks: These landmarks represent actual anatomic structures of the skull. E.g. Nasion, ANS, PNS, orbitale, pogonion, etc.  Derived landmarks: These are landmarks that have been srbitrarily obtained secondarily from anatomic structures in a cephalogram. E.g. Sella, gnathion, articulare, point PTM, machine porion, etc. They are not anatomical points.  Gnathion: Gnathion is a coonstructed point at the junction of most anterior (Pogonion) and most inferior  part (menton) of the chin.  CLICK HERE TO VIEW MORE MCQs