TABLE 1

Cephalometric points identified on each lateral cephalograph

TraitAbbreviationDescription
1. ArticulareArThe intersection of the image of the posterior border of the ramus with the external surface of the basicranium
2. BasionBaThe anterior margin of the foramen magnum
3. NasionNThe intersection of the nasal and frontal bones
4. Posterior nasal spinePNSThe posterior point of the hard palate
5. ProsthionPrThe anterior point of the premaxilla between the upper central incisors
6. SellaSThe pituitary fossa of the sphenoid bone
7. GonionGoaThe external angle of the mandible
8. MentonMeThe most inferior point on the mandibular symphysis
9. GnathionGnThe lowest, most anterior point on the mandibular symphysis
10. Posterior condylionPCdThe point tangent to a perpendicular line extending from the S–N plane
11. InfradentaleIdThe anterior point of the tip of the alveolar process of the mandible between the lower central incisors
12. Point DDThe center of the cross-section of the mandibular symphysis
13. PogonionPogThe most anterior point of the mandibular symphysis
14. Pterygomaxillary fissurePTMaTeardrop-shaped area between maxilla and pterygoid process of the sphenoid
15. Center of faceCFaPosterior-most point of the pterygomaxillary fissure
16. OrbitaleOraInferior-most point of the orbit
17. PorionPoaSuperior margin of external auditory canal
18. Frankfort horizontalFHaPlane defined by right and left porion and left orbitale
19. Facial planeFPLine connecting nasion and pogonion
20. XnnnPoints defined along the endocranial surface of the neurocranium relative to the S–N plane (e.g., X100 is the point at which a line drawn 100° from the S–N plane intersects the endocranium)
  • All points represent midline structures except where noted.

  • a Points not on midline of the skull.