Table 2. Descriptive statistics of patient-centered variables of questions 1 and 2 at five assessment times in the two groups using the Visual Analog Scale and the results of significance test†.

^†Employing independent samples t-test or Mann-Whitney test. SD: standard deviation, Min: minimum, Max: maximum, CI: confidence interval, T1: 24 hours after the beginning of the expansion, T2: 7 days after, T3: 15 days after, T4: 1 month after, T5: 4 months after the onset of expansion, RME: rapid maxillary expansion, SME: slow maxillary expansion, (NS): there was no statistically significant difference at P > 0.05, (*): there was a statistically significant difference at P < 0.001.

	Group	Mean	SD	Min	Max	95% CI for difference		P-value	Significance
						Lower bound	Upper bound
Q1: Pain and discomfort
T1 (24 h)	RME	66.37	12.71	33.00	87.00	61.34	71.40	<0.001	*
	SME	32.16	11.32	12.00	48.00	27.48	36.83
T2 (7 d)	RME	51.07	12.72	18.00	71.50	46.03	56.10	<0.001	*
	SME	16.46	6.84	4.00	32.50	13.63	19.28
T3 (15 d)	RME	27.46	12.32	2.50	48.50	22.58	32.33	<0.001	*
	SME	12.14	6.39	1.00	27.50	9.49	14.78
T4 (1 m)	RME	12.44	5.46	4.50	23.50	10.28	14.60	0.097	(NS)
	SME	9.24	6.25	0.00	25.50	6.65	11.82
T5 (4 m)	RME	5.92	5.03	0.00	14.50	3.93	7.91	0.338	(NS)
	SME	8.28	6.19	0.00	24.50	5.72	10.83
Q2: Chewing difficulties
T1 (24 h)	RME	47.94	10.16	32.50	67.00	43.92	51.96	0.001	*
	SME	23.94	4.74	17.00	33.50	21.98	25.89
T2 (7 d)	RME	44.90	10.22	28.50	64.00	40.86	48.95	0.001	*
	SME	19.94	4.74	13.00	29.50	17.98	21.89
T3 (15 d)	RME	39.05	10.00	25.00	58.00	35.09	43.01	<0.001	*
	SME	17.94	4.74	11.00	27.50	15.98	19.89
T4 (1 m)	RME	19.68	9.71	5.00	38.00	15.84	23.52	0.001	*
	SME	14.94	4.74	8.00	24.50	12.98	16.89
T5 (4 m)	RME	0.22	0.50	0.00	2.00	0.02	0.42	0.238	(NS)
	SME	1.58	3.79	0.00	16.00	0.01	3.14