Table 1.

Definition of Cephalometric Measurements Used in This Study^a

Measurement	Definition
Sagittal parameters
SNA, °	Sella-nasion-A point angle
SNB, °	Sella-nasion-B point angle
ANB, °	A point-nasion-B point angle
VRP-Pog, mm	Perpendicular distance of pogonion to the vertical reference plane (VRP)
OJ, mm	Overjet, parallel distance between the incisal edges of U1 and L1 to the horizontal reference plane (HRP)
Vertical parameters
SN-GoMe, °	Mandibular plane angle, the angle between sella-nasion line and gonion-menton line
AFH, mm	Anterior facial height, linear distance between nasion and menton
OB, mm	Overbite, parallel distance between the incisal edges of U1 and L1 to the VRP
Tooth movement
U6-PP, mm	Perpendicular distance of the mesial cusptip of U6 to the palatal plane (PP)
U1-PP, mmb	Perpendicular distance of U1 incisal edge to the PP
L6-MP, mm	Perpendicular distance of the mesial cusptip of L6 to the mandibular plane (MP)
L1-MP, mmb	Perpendicular distance of L1 incisal edge to the MP

^aU1 and L1 indicate the maxillary and mandibular central incisor, respectively; U6 and L6, the maxillary and mandibular first molar, respectively.

^bThe most anterior tooth was used for the measurement.