Geometrical Approaches for the Accurate Identification of Normal Vertical Positions of Sella and Nasion Points in Cephalograms

Figure 3

Angular parameters. (1) ∠Ba-S-Ptm, the angle between Ba, S and Ptm; (2) ∠Ba-S-PNS, the angle between Ba, S and PNS; (3) ∠Ar-S-Ptm, the angle between Ar, S and Ptm; (4) ∠Ar-S-PNS, the angle between Ar, S and PNS; (5) ∠S-Ba-PNS, the angle between S, Ba, and PNS; (6) ∠S-Ba-Ptm, the angle between S, Ba, and Ptm; (7) ∠S-Ar-PNS, the angle between S, Ar and PNS; (8) ∠S-Ar-Ptm, the angle between S, Ar and Ptm; (9) ∠S-PNS-Ba, the angle between S, PNS and Ba; (10) ∠S-PNS-Ar, the angle between S, PNS and Ar; (11) ∠S-Ptm-Ba, the angle between S, Ptm and Ba; (12) ∠S-Ptm-Ar, the angle between S, Ptm and Ar.