Predictability of crowding resolution in clear aligner treatment

Progress in Orthodontics

Table 2 Comparison between T0, T1v, and T1 in upper arch

Variables	T0		v T1		T1		Shapiro–Wilk	Predictability (%)	p
Variables	Mean	SD	Mean	SD	Mean	SD	Shapiro–Wilk	Predictability (%)	p
Irregularity Index	7.26	3.30	1.83	0.65	2.81	1.72	0.40	87.0	0.04*
3-3 width	23.53	2.55	24.83	2.01	24.20	1.95	0.90	59.0	0.03*
4-4 width	26.08	2.50	28.10	2.40	27.20	2.26	0.96	60.0	0.02*
5-5 width	30.74	2.62	32.67	2.67	31.93	2.60	0.77	68.0	0.01*
6-6 width	33.24	3.21	34.74	2.93	34.40	2.94	0.86	83.0	0.00*
Arch length	28.40	2.29	27.27	2.17	27.67	2.31	0.93	68.0	0.04*
IPR	–	–	1.09	1.13	0.55	0.64	0.85	49.0	0.02*