Cephalometrics Flashcards
what is nasion
most anterior point of the fronto nasal suture
what is sella
midpoint of pituitary fossa
what is point A
point at the deepest midline concavity on the anterior maxilla
what is the anterior nasal spine
tip of the bony anterior nasal spine
what is the posterior nasal spine
tip of the posterior nasal spine
what is point B
point at the deepest concavity on the mandibular symphysis
what is pogonion
most anterior point of the mandibular symphysis
what is menton
most inferior point of the mandibular symphysis
what is gonion
intersection of tangents of the ramus plane and the mandibular plane
most posterior and inferior point of the angle of the mandible
what is the SNA angle
antero-posterior positioning of the maxilla in relation to cranial base
what does increased SNA angle indicate
prognathic maxilla
what does decreased SNA angle dictate
retrognathic maxilla
what does SNB angle indicate
antero-posterior positioning of the mandible in relation to the cranial base
what does increased SNB angle indicate
prognathic mandible
what does decreased SNB angle indicate
retrognathic mandible
what does the ANB angle denote
position of maxilla and mandible to each other
what does an increased ANB angle indicate
class II skeletal pattern
what does a decreased ANB angle indicate
class III skeletal pattern
what is the maxillo-mandibular plane angle
formed by intersection of the mandibular and maxillary plane
what does an increased MMPA indicate
vertical growth pattern
what does a reduced MMPA indicate
horizontal growth pattern
what is the E plane
ricketts esthetic plane
what does the E plane line join
soft tissue chin and nose tip
in a balanced face what is the lower and upper lip distance to the E plane
lower lip - 1-2mm
upper lip - 2-3mm
