Table 2.

Clinical and cephalometric characteristics at baseline (T1) and at follow-up (T2) after an average of 7 years of OA use.

	Mean ± SD			Significance,a P
	T1	T2	T2–T1
Clinical crown height (mm)
Lower left canine	9.61 ± 1.35	9.84 ± 1.54	0.24 ± 0.45	.025
Lower left lateral incisor	8.24 ± 1.22	8.41 ± 1.31	0.16 ± 0.47	.136
Lower left central incisors	7.86 ± 1.19	7.89 ± 1.18	0.03 ± 0.58	.839
Lower right central incisor	8.14 ± 1.39	7.97 ± 1.43	0.17 ± 0.60	.218
Lower right lateral incisor	8.45 ± 1.06	8.49 ± 1.29	0.05 ± 0.60	.730
Lower right canine	9.95 ± 1.42	9.93 ± 1.40	–0.02 ± 0.42	.828
Lower incisors onlyb	8.17 ± 1.21	8.19 ± 1.31	0.02 ± 0.57	.781
Overjet (mm)	3.38 ± 1.65	2.14 ± 1.81	–1.24 ± 1.59	.001
Overbite (mm)	3.21 ± 1.40	2.19 ± 1.71	–1.02 ± 0.96	< .001
Cephalometric variables
ANB (degrees)	4.02 ± 2.50	4.46 ± 2.24	0.44 ± 0.87	.032
Sn-GoGn (degrees)	28.81 ± 6.85	29.69 ± 6.72	0.88 ± 1.51	.015
FMA (degrees)	23.74 ± 5.73	24.60 ± 5.60	0.85 ± 1.36	.009
IMPA (degrees)	95.81 ± 11.26	100.95 ± 11.88	5.13 ± 3.60	< .001
L1-NB (mm)	4.92 ± 2.25	6.05 ± 2.42	1.13 ± 0.77	< .001
L1-NB (degrees)	25.70 ± 7.46	31.10 ± 8.73	5.41 ± 3.89	< .001

^aPaired t test for normally distributed data and Wilcoxon signed-rank test for nonparametric data. ^bThe mean clinical crown height of the lower incisors only not including the canines n = 83. ANB = angle between point A, nasion, point B; FMA = angle between Frankfort’s horizontal plane and mandibular plane, IMPA = angle between long axis of most proclined mandibular incisor and mandibular plane (Go-Gn), L1-NB = linear measurement from line NB to most labial portion of the crown of mandibular incisor, L1-NB = angle between long axis of mandibular incisor and line from nasion to point B, OA = oral appliance, Sn-GoGn = angle between SN plane and mandibular plane (Go-Gn).