A prospective clinical trial of the effects produced by the extrusion arch in the treatment of anterior open bite

Progress in Orthodontics

Table 3 Mean values with standard deviations and 95% confidence intervals (CI) of variables at T0 and T1 achieved with the extrusion arch mechanics with mean differences (T1–T0)^a

Variable	T0 (initial)		T1 (Final)		T1–T0		CI (95%)
	Mean	SD	Mean	SD	Mean	SD	UB	LB	P value
Interincisal angle (°)	115.58	7.04	121.15	10.57	5.57	6.59	1.77	9.38	.010*
U1.PP (°)	115.73	4.40	109.58	5.96	− 6.15	6.42	− 9.85	− 2.44	.003*
U1-PP (mm)	25.45	3.38	27.39	2.77	1.94	1.71	0.96	2.93	.001*
U1 tip-U6D (mm)	40.82	2.56	38.61	3.65	− 2.21	2.34	− 3.57	− 0.84	.004*
U6-PP (mm)	17.86	1.94	16.85	2.38	− 1.01	3.22	− 2.86	0.85	.260
U6.PP (°)	86.56	10.47	75.07	7.26	− 11.49	8.41	6.63	16.34	< .0001*

^aLB indicates lower bound, UB upper bound, SD indicates standard deviation, U1 maxillary central incisor, U6 maxillary first molar, U6D distal aspect of maxillary first molar
*P < .05