Volumetric Analysis of the Jaws in Skeletal Class I and III Patients with Different Facial Divergence Using CBCT Imaging

Table 1

The linear and angular measurements measured on the CBCT-derived cephalometric images.

SNA	The sagittal position of the maxilla in relation to the base of the skull
SNB	The sagittal position of the mandible in relation to the base of the skull
ANB	The difference between the above two angles, it represents the sagittal relationship between the jaws
Y-axis	The angle that is formed from the points (N-S-Gn) according to Jarabak
MM angle	The angle between the maxillary and mandibular planes
Md.SN	(S-N : Go-Me) The angle between the mandibular plane and the anterior basal plane
Mx.SN	(S-N : Spp) The angle between the maxillary plane and the anterior basal plane
N-Me	The anterior facial height (mm)
S-Go	The posterior facial height (mm)
N-Go	The facial depth (mm)
Bjork sum	(N-S-Ar) The sella angle between the anterior and posterior basal planes
	(S-Ar-Go) The articular angle between the posterior basal plane and the ramus
	(Ar-Go-Me) The angular angle between the ramus and the mandibular plane
	The sum of Bjork is the sum of the above angles according to Bjork

The definitions were based on A. Jacobson and R. L. Jacobson [23] and Riolo et al. [24].