Table 1 Cephalometric landmarks and lines used to identify craniofacial structures and adenoids
Abbreviation | Name | Description |
|---|---|---|
Cephalometric points | ||
A | A-point | The deepest point of the concavity of the anterior maxilla between ANS and the alveolar crest |
Aa | Anterior atlas | The most anterior point of the atlas |
Ad | Adenoids | The intersection between PNS-Ba and the anterior border of the adenoids |
H | Hyoid | The most anterior–superior point on the body of the hyoid bone |
ANS | Anterior nasal spine | The anterior tip of the bony apex of the maxillary complex |
B | B-point | The deepest point in the concavity of the anterior mandible between the alveolar crest and the bony chin |
Ba | Basion | The most inferior point of the anterior border of the foramen magnum |
C2ai | 2nd cervical vertebra A | The most anterior–inferior point of the second cervical vertebra |
C2pi | 2nd cervical vertebra B | The most posterior–inferior point of the second cervical vertebra |
C2ps | 2nd cervical vertebra C | The most posterior–superior point of the second cervical vertebra |
C3ai | 3rd cervical vertebra | The most anterior–inferior point of the third cervical vertebra |
C4pi | 4th cervical vertebra | The most posterior–inferior point of the fourth cervical vertebra |
Cd | Condylion | The most posterior–superior point on the mandibular condyle |
Gn | Gnathion | The most anterior–inferior point on the bony chin |
Go | Gonion | The intersection of the tangents to the inferior and posterior borders of the mandible |
U4 | Maxillary first premolar cusp | The cusp tip of the maxillary first premolar |
L4 | Mandibular first premolar cusp | The cusp tip of the mandibular first premolar |
U6 | Maxillary first molar cusp | The mesial cusp tip of the maxillary first permanent molar |
L6 | Mandibular first molar cusp | The mesial cusp tip of the mandibular first permanent molar |
Me | Menton | The most inferior point on the body chin |
N | Nasion | The most anterior point of the fronto-nasal suture |
Sy | Spheno-occipital synchondrosis | The anterior border of the spheno-occipital synchondrosis |
Or | Orbitale | The most inferior point of the inferior borders of the bony orbit |
Pm | Pterygo-maxillare | The most inferior point of the pterygomaxillary fissure |
PNS | Posterior nasal spine | The posterior tip of the bony apex of the maxillary complex |
Po | Porion | The most superior point of the external auditory meatus |
S | Sella | The geometric centre of the sella turcica |
Cephalometric lines | ||
CV | Cervical vertebrae | The line joining C2ai and C3ai |
AaL | Anterior atlas line | The line perpendicular to MxP and passing through Aa |
EsfL | Sphenoid line | The line tangent to the inferior border of the sphenoid bone and passing through Ba |
FH | Frankfort horizontal plane | The line joining Or and Po |
MnP | Mandibular plane | The line joining Me and Go |
MxP | Maxillary plane | The line joining ANS and PNS |
OP | Occlusal plane | The line joining the midpoint between U4 and L4 with the midpoint between U6 and L6 |
OPT | Odontoid process tangent | The line joining C2ps and C2pi |
PmL | Pterygomaxillary line | The line perpendicular to MxP and passing through Pm |
BasL | Basioccipital line | The line representing the anterior margin of the basioccipital bone |