Table 2.

Changes in the transverse dentoskeletal variables after rapid maxillary expansion (RME)

Dentoskeletal variables	T-RME				H-RME				Intergroup p value‡
	T1	T2	Change	Intragroup p value†	T1	T2	Change	Intragroup p value†
Facial width (mm)	140.78 ± 5.03	140.83 ± 5.50	0.04 ± 1.26	0.366	141.46 ± 6.22	141.65 ± 6.29	0.19 ± 0.63	0.211	0.772
Nasal width (mm)	34.23 ± 3.16	34.90 ± 3.32	0.67 ± 1.19	0.023	33.34 ± 2.25	35.64 ± 2.46	2.30 ± 1.11	< 0.001	< 0.001
Maxillary width (mm)	66.52 ± 3.58	67.88 ± 3.77	1.35 ± 1.41	< 0.001	67.52 ± 3.69	70.31 ± 3.94	2.79 ± 1.59	< 0.001	0.003
Intermolar root width (mm)	50.62 ± 2.68	53.43 ± 3.14	2.82 ± 2.09	< 0.001	51.11 ± 3.55	55.18 ± 4.19	4.07 ± 1.92	< 0.001	0.024
Intermolar crown width (mm)	59.18 ± 2.81	64.97 ± 3.37	5.79 ± 1.89	< 0.001	59.05 ± 4.06	64.37 ± 5.13	5.32 ± 2.05	< 0.001	0.222

Data are presented as 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