Cephalometric Analysis Normal Values

Steiner SNA

±82° 

Steiner SNB

±80° 

Steiner ANB

±2° 

Steiner mandibular plane angle

±32° 

Steiner occlusal plane angle

±14° 

Upper incisor to NA: angular

±22°

Upper incisor to NA: linear

±4 mm

Lower incisor to NA: angular

±25° 

Lower incisor to NA: linear

±4mm

Steiner inter-incisal angle

±130° 

Down’s facial angle

130° 

Down’s angle of convexity

−8.5 to 10° 

Down's A-B plane angle

−9 to 0° 

Down's mandibular plane angle

17–28° 

Down's Y-axis

53–66° 

Down's cant of occlusal plane

1.5–14° 

Down's inter-incisal angle

130–150.5° 

Down's incisor occlusal plane angle

3.5–20° 

Down's incisor mandibular plane angle

−8.5 to 7° 

Down's upper incisor to A-Pog line

−1 to 5 mm

Frankfort Mandibular Plane Angle (FMA)

25∘ (16∘−35∘16∘−35∘).

Incisor Mandibular Plane Angle (IMPA)

90∘ (85∘−95∘85∘−95∘)

Frankfort Mandibular Incisor Plane Angle (FMIA)

65∘ (60∘−75∘60∘−75∘).