Table 4.

Changes in the soft tissue variables after rapid maxillary expansion (RME)

Soft tissue variables	T-RME				H-RME				Intergroup p value‡
	T1	T2	Change	Intragroup p value†	T1	T2	Change	Intragroup p value†
Alar width (%)	58.91 ± 3.93	59.79 ± 3.75	0.88 ± 1.73	0.023	60.79 ± 3.74	61.98 ± 4.06	1.18 ± 1.52	0.004	0.624
Nose length (%)	79.77 ± 5.22	79.74 ± 5.66	− 0.02 ± 2.07	0.848	81.41 ± 4.91	82.39 ± 4.97	0.98 ± 2.32	0.025	0.204
Upper lip length (%)	36.67 ± 3.44	37.50 ± 3.17	0.84 ± 1.78	0.030	37.15 ± 5.03	37.53 ± 4.59	0.38 ± 1.75	0.434	0.505
Lip chin length (%)	73.88 ± 5.09	74.55 ± 5.68	0.67 ± 3.04	0.394	78.07 ± 9.26	77.13 ± 8.76	− 0.94 ± 3.65	0.375	0.232
Upper lip vermilion (%)	14.98 ± 1.93	15.09 ± 2.15	0.11 ± 1.02	0.476	15.53 ± 1.88	15.18 ± 1.83	− 0.35 ± 1.02	0.181	0.213
Lower lip vermilion (%)	18.33 ± 3.04	18.37 ± 2.64	0.04 ± 1.53	0.958	19.21 ± 2.98	19.60 ± 2.91	0.39 ± 1.34	0.192	0.538

Data are presented as a percentage of the interpupillary distance in the form of mean ± standard deviation

T-RME, the group who received RME procedure with the conventional tooth-born expander; H-RME, the group underwent RME using the tooth-bone-borne hybrid expander; T1, pretreatment; T2 after RME (at least 6 weeks after fixation of the expander); Change, change in each variable after RME

^†The Wilcoxon signed-rank test was used to analyse the significance of changes in the variables within a group

^‡The Mann–Whitney U test was used to analyse the significance of differences in changes between the groups