Table 2.

Comparison of frontal distances after mandibular setback operations (SSROvs. IVRO).

		Postoperation changes
		SSRO				IVRO				SSRO vs.IVRO
Bilateral sides		Mean	SD	p value		Mean	SD	p value		p value
Bone plane	0	1.9	3.07	0.0030	∗	4.4	3.51	< 0.0001	∗	0.0040	†, IVRO > SSRO
	1	1.9	2.91	0.0012	∗	4.7	4.14	< 0.0001	∗	0.0044	†, IVRO > SSRO
	2	2.7	2.79	< 0.0001	∗	3.3	4.91	0.0010	∗	0.5938	—
	3	3.2	4.07	0.0002	∗	-0.9	7.37	0.5005	—	0.0207	†, SSRO > IVRO
Muscle plane	0	0.1	4.29	0.8846	—	0.9	3.84	0.2341	—	0.6025	—
	1	0.9	3.90	0.2505	—	0.7	4.10	0.3548	—	0.7963	—
	2	0.9	4.24	0.2606	—	0.0	4.03	0.9648	—	0.3837	—
	3	1.2	5.75	0.2578	—	-0.5	6.19	0.6877	—	0.2604	—
Skin plane	0	0.5	4.14	0.5345	—	1.2	5.18	0.2284	—	0.6785	—
	1	-0.5	4.09	0.5580	—	0.3	5.61	0.7874	—	0.6460	—
	2	0.2	5.18	0.8635	—	-0.9	5.75	0.4063	—	0.4108	—
	3	1.3	5.00	0.1720	—	-1.4	6.70	0.2751	—	0.0995	—

∗: intragroup comparison: statistically significant, p < 0.05.

†: intergroup comparison: statistically significant, p < 0.05.

—: not significant.