Table 9.

Correlation between each demographic factors and all smile variables in frontal, three-quarter, and lateral views by using multivariate logistic regression (cont'd).

Characteristic		UDM	BC	MGD	Cant	ULT	MA	NLA
		frontal	frontal	frontal	frontal	lateral	lateral	Lateral
Gender	Men
	Women	−0.02	0.09	−0.24	0.16∗	0.12	−0.28∗∗	−0.07
Age (y/o)	20–30
	31–40	−0.15	0.07	−0.19	0.11	−0.16	−0.30	−0.11∗
	>40	−0.34	−0.56∗	−0.10	−0.01	0.04	−0.14	0.01
Identity	LP
	GD	−0.11	−0.20∗	0.25∗∗	−0.11∗∗∗	0.20	0.15∗∗	0.74∗∗
	Ortho	−0.14	−0.11	0.37∗∗	−0.14∗∗∗	−0.08	0.04∗∗	0.17∗∗
Treatment	w/o T
	T	−0.20∗	0.14	−0.12	−0.14	0.10	−0.10	−0.22∗∗∗
Salary	<20 T
	20–40 T	−0.34∗∗	−0.01	−0.13	0	−0.13	−0.07	−0.12
	40–60 T	−0.33∗	−0.29	−0.08	0.15	0.06	0.05	0.13
	60–80 T	0.01	0.07	0.01	−0.15	−0.47∗	−0.15	−0.16
	>80 T	−0.09	0.07	−0.16	−0.13	−0.23	0.14	−0.01

UDM: upper dental midline, BC: buccal corridor, MGD: maxillary gingival display, ULT: upper lip thickness, MA: mouth angle, NLA: nasolabial angle, LP: laypeople, GD: general dentist, Ortho: orthodontist, w/o T: without treatment, T: treated.

Starred mark: statistical significance (P < 0.05) and correlation were revealed ∗P < 0.05, ∗∗P < 0.01, ∗∗∗P < 0.001.