Correlation between the Rotation of the First Molars and the Severity of Class II Division 1 Malocclusion

Table 1

Points, lines, and angles used to evaluate molar rotation.

	Definition
Points
RP1	Most anterior region of the palatine raphe
RP2	Most posterior region of the palatine raphe
MV	Tip of the mesiobuccal cusp of the maxillary first molar
DV	Tip of the distobuccal cusp of the maxillary first molar
MP	Tip of the mesiopalatal cusp of the maxillary first molar
C	Tip of the cusp of the maxillary canine
Lines
Line MV-DV	Connection between points MV and DV
Line RP1-RP2	Connection between points RP1 and RP2
Line DV-MP	Connection between points DV and MP (line of Ricketts)
Angles
Angle of Henry	Angle formed between MV-DV and RP1-RP2 lines
Angle of Friel	Angle formed between the palatine raphe and the MP-MV line