4. cephalometric landmarks are readily
recognizable points on a cephalometric
radiograph or tracing, representing certain
hard or soft tissue anatomical structures
(anatomical landmarks) & (constructed
landmarks).
5. Should be easily seen on the roentgenogram,
Be uniform in out line, and easily reproducible.
Should have significant relationship to the
vectors of growth.
Should permit valid quantitative
measurements of lines and angles projected
from them.
Measurements should be amenable to
statistical analyses.
8. These lines are obtained by connecting two
landmarks.
Based on their orientation the lines or planes
can be classified into horizontal and vertical.
LINES AND PLANES IN
CEPHALOMATRICS
10. VERTICAL PLANE
• A – Pog line
• Facial plane
• Facial axis
• Esthetic plane (E-plane)
Editor's Notes
Nasion-most anterir point midway btwn the frontal nd nasal bones on the fronto-nasal suture.
Orbitale-lowest point on the inferior bony margin of the orbit.
Porion-highst bony point on the upper margin of external auditory meatus.
Sella-the point representing the midpoint of the pituitry fossa/sella turcica,it is constructed point in mid-sagittal plane.
A-the deepst point in midline btwn the anterior nasal spine nd alveolar crest btwn the 2 central incisors.(subspinale).
B-deepst point in the midline btwn the alveolr crest of mandible nd mental process(supramentale).
Basion-the median point of the anterior margin of foramen magnum.
Bolton point-highst point at the post condylar notch of occipital bone.
Anterior nasal spine-anterir tip of the sharp bony process of the maxilla in the midline of th lower margin of anterior nasal openin.
Gonion-a constructed point at the junction of ramal plane nd mandi plane.
Pogonion-most anterior point of the chin in the median plane.
Menton-most inferior midline point on the mandi symphysis.
Gnathion-most antero-inferior point on the symphysis of chin,constructd by intersectin a line drawn perpendiclr to the line connectin menton nd pogonion.
Articulare-is a point at the junction of the posterir bordr of ramus and inferior border of the basilar part of the occipital bone.
Condylion-most superior point on the head of the condyle.
Prosthion-lowest nd most anterior point on the alveolar bone in the midline,btwn upper centrl incisors( also called supradental
Infradentale-highst nd most anterior point on the alveolar process,in the midline btwn the mandi central incisors.
PNS-is the intersection of a continuation of the anterior wall of the pterygo-palatine fossa nd the floor of the noe, marking the distal limit of the maxilla.
Ptm point-is the intersection of the inferior border of the foraman rotundum with the posterior wall of the pterygo-maxillary fissure.
Glabella-is the most prominent point in the midsagital plane of forehead.
Nasion soft tissu-is the deepest point in the concavity of the soft tissue contour of the root of the nose.
Pronasale-most prominent point of the nose.
Subnasale-is the intersection of the lower border of the nose nd the outer contour of the upper lip.
Labrale superius-median point in the upper margin of the upper membranous lip.
Superior labial sulcus-point of greatest concavity in the midline of the upper lip.
Stomion superius-lowest point of the upper lip.
Stomion inferius-highest point of the lower lip.
Stomion-is the midpoint btwn stomion superius nd stomion inferius.
Labrale inferius-median point in the lower margin of the lower membranous lip.
Inferior labial sulcus-greatest concavity in the midline of the lower lip.
Pogonion soft tissu-most prominent point on the soft tissue of chin.
Menton soft tissue-point in the inferior soft tissue of the chin.
Sella nasion plane -is the cranialline btwn the center of sella nd the anterior point of the fronto-nasal suture(nasion)-it represent the anterior cranial base.
Frankfort horizntal plane –the plane cconnects the lowest point of the orbit(ortitale) nd the superior point of the external auditory meatus(porion).
Occlusal plane –is a plane bisecting the posterior occlusion of molars nd premolars which extends to anteriors.
Palatel plane –line conecting ans of maxilla nd posterior nasal spine off maxilla.
Mandibula plane –a) tangent to lower border of the mandible(tweed)
b) a line connectin gonion nd gnation (steiner)
c) line connectin gonion nd menton. (Down)
A-pog line – line from point A on maxilla nd pogonion in mandible.
Facial plane – it’s a line from the most anterior point of frontonasal suture(nasion) to most anterior point of mandi (pogonion).
Facial axis –line from ptm to gnathion.
E –plane – line btwn the most anterior point of the soft tissue nose nd the soft tissue chin.
