intro to cephs Flashcards
sella
1) geometric center of the pituitary fossa
- very important!
1) midline structure in cranial base (anchor point)
nasion
1) anterior point of frontonasal suture in midsagittal plane
2) not necessarily the most concave part
anterior nasal spine
1) anterior tip of the sharp bony process of the maxilla at the lower margin of the anterior nasal opening
2) do not confuse cartilage for ANS
posterior nasal spine
1) posterior spine of the palatine bone constituting the hard palate
2) with ANS it can measure the angle of the upper jaw
point A
1) also known as subspinale
2) most posterior midline point in the concavity between the ANS and the prosthion
3) where the upper jaw is
point B
1) supramentale
2) posterior midline point in the concavity of the mandible between infradentale and pogonion
pogonion
1) anterior point of the chin
2) cannot usually tell where the jaw is
gnathion
1) midpoint between pogonion and inferior menton points of the bony chin
2) look at plane of lower jaw
menton
1) lowest point on the symphyseal shadow of the mandible seen on a lateral ceph
gonion
1) curvature of the angle of mandible located by bisecting the angle formed by lines tangent to the posterior ramus and the inferior border of the mandible
2) look at plane of lower jaw
3) may see a double border if there is asymmetry
measurements
1) cranial base
2) sagittal
3) vertical
4) dentoalveolar
5) soft tissue
- compare to a norm and then determine cephalometric diagnosis
- depends on ethnicity
S-N-Ar
1) flexure of cranial base which can affect A-P position of the jaws
sagittal measurements
1) SNA
- upper jaw
- 82 degree
2) SNB
- lower jaw
- 80 degree
3) wits
-1 - 0 is normal
>0 is class II
<-1 is class III
4) angle of convexity
- N-A-Pog
- measures profile (straight, convex, concave)
vertical measurements
1) S-N-Palatal plane (PP)
2) S-N-occlusal plane (OP)
3) S-N-Md plane (MP)
4) % LFH (ANS-Me/N-Me)
- all angular measurements except %LFH
dentoalveolar measurements
1) U1-S-N
2) U1-N-A
3) L1-N-B
4) L1-MP
5) L1-A-Pog
6) interincisal angle
7) Pog-N-B