Table 1.

Baseline characteristics of study patients in the control and test groups (n = 61)

Variable	Control group (n = 30)	Test group (n = 31)	p-value
Sex			0.30
Female	23 (76.7)	20 (64.5)
Male	7 (23.3)	11 (35.5)
Age (yr)	16.0 ± 3.18	18.0 ± 5.14	0.074
Little’s irregularity index (LII) before orthodontic treatment (mm)	4.20 ± 2.15	3.98 ± 2.51	0.72

Values are presented as mean ± standard deviation for continuous variables and as frequencies (number, %) for categorical variables.

Chi-square test for the comparison of the sex proportion between groups.

Two-sided unpaired Student’s t-test for the comparison of the age and LII means between groups.