Table 5.

Descriptive statistics of periodontal variables according to intervention groups at different timepoints

Variables	Timepoint	RPE (N = 17)	MARPE (N = 19)	P value
PM-BBPT (mm)	T1-T0	− 0.73 ± 0.36†	− 0.45 ± 0.30†	0.016*
	T2-T1	− 0.25 ± 0.47	0.01 ± 0.39	0.076
	T2-T0	− 0.96 ± 0.44†	− 0.43 ± 0.38†	< 0.001*
PM-PBPT (mm)	T1-T0	1.09 ± 0.89††	0.64 ± 0.56††	0.087
	T2-T1	0.05 ± 0.52	− 0.28 ± 0.58	0.083
	T2-T0	1.16 ± 0.62††	0.35 ± 0.43††	< 0.001**
M-BBPT (Mesial root) (mm)	T1-T0	-0.55 ± 0.39††	− 0.57 ± 0.39††	0.707
	T2-T1	− 0.38 ± 0.30††	0.05 ± 0.32	< 0.001**
	T2-T0	− 0.91 ± 0.40†	− 0.45 ± 0.56†	0.007*
M-BBPT (Distal root) (mm)	T1-T0	− 0.60 ± 0.34†	− 0.63 ± 0.36†	0.824
	T2-T1	− 0.31 ± 0.35	0.03 ± 0.29	0.005**
	T2-T0	− 0.90 ± 039†	− 0.54 ± 0.57†	0.032*
M-PBPT (mm)	T1-T0	0.80 ± 0.61††	0.63 ± 0.32††	0.661
	T2-T1	0.32 ± 0.32	− 0.08 ± 0.38	0.001**
	T2-T0	1.10 ± 0.57†	0.55 ± 0.30†	0.001*

Descriptive statistics represented as mean ± standard deviation

^†Indicate statistical significance with repeated measures analysis of variance with Bonferroni correction (α = 0.016)

^†† Indicate statistical significance with Friedman’s analysis of variance by ranks (α = 0.05)

*Indicate statistical significance with independent t-test at each time point (P < 0.05)

**Indicate statistical significance with Mann–Whitney U test at each time point (P < 0.05)

Abbreviations: RPE, rapid palatal expansion; MARPE, mini-screw assisted rapid palatal expansion; T0, before treatment; T1, immediately after expansion; T2, after a 3-month consolidation period