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

Table 2

Various linear parameters and ratio used to determine the normal vertical positions of S and N points.

Variables	Gender	Values mean ± SD	Significance ( value); Males vs females
S-Ba distance (mm)	Males	45.69 ± 3.13	0.000^∗∗∗
	Females	42.75 ± 2.96
	Total	44.10 ± 3.36
S-Ar distance (mm)	Males	35.46 ± 2.89	0.000^∗∗∗
	Females	32.37 ± 2.70
	Total	33.79 ± 3.18
S-Ptm distance (mm)	Males	35.98 ± 3.04	0.000^∗∗∗
	Females	33.27 ± 2.44
	Total	34.52 ± 3.04
S-PNS distance (mm)	Males	46.44 ± 3.38	0.000^∗∗∗
	Females	43.33 ± 2.68
	Total	44.77 ± 3.38
Ar-Ptm distance (mm)	Males	35.26 ± 3.01	0.000^∗∗∗
	Females	32.78 ± 2.21
	Total	33.92 ± 2.88
Ar-PNS distance (mm)	Males	38.78 ± 3.23	0.000^∗∗∗
	Females	36.22 ± 2.55
	Total	37.40 ± 3.14
Ba-Ptm distance (mm)	Males	43.80 ± 3.39	0.000^∗∗∗
	Females	41.54 ± 2.81
	Total	42.58 ± 3.25
Ba-PNS distance (mm)	Males	44.70 ± 6.66	0.060^∗
	Females	42.94 ± 2.96
	Total	43.75 ± 5.07
S-FH distance (mm)	Males	18.28 ± 2.26	0.000^∗∗∗
	Females	16.70 ± 1.93
	Total	17.43 ± 2.23
N-FH distance (mm)	Males	26.33 ± 2.41	0.053^NS
	Females	25.51 ± 2.16
	Total	25.89 ± 2.30
S-FH:N-FH ratio (%)	Males	0.69 ± 0.07	0.002^∗∗
	Females	0.65 ± 0.06
	Total	0.67 ± 0.06

Ba, basion; Ar, articulare; S, sella; Ptm, pterygomaxillary fissure; PNS, posterior nasal spine; FH, Frankfort horizontal plane. SD = standard deviation, NS = nonsignificant, ^∗ =  ,^∗∗ =  , ^∗∗∗ = .