Table 3.

Intraclass correlation coefficient (ICC) in MZ, DZ, and sibling groups

Variables	ICCMZ	ICCDZ	ICCSib
Bisected OP (to SN)	0.83***	0.64*	0.62**
Bisected OP (to FH)	0.85***	0.35	0.48
Functional OP (to SN)	0.75***	0.49	0.57
Functional OP (to FH)	0.79***	0.41	0.36
MM bisector OP (to SN)	0.87***	0.66*	0.68*
MM bisector OP (to FH)	0.86***	0.59	0.51
Mn. plane angle (to SN): MR	0.87***	0.62	0.55
Mn. plane angle (to FH)	0.86***	0.49	0.41
Palatal plane angle (to SN)	0.82***	0.48	0.65*
Palatal plane angle (to FH)	0.82***	0.53	0.53*
Corpus axis (to SN): TR	0.85***	0.61	0.45
Corpus axis (to FH)	0.81***	0.51	0.24
Corpus axis (to MP): IR	0.74**	0.67*	0.24

MZ Monozygotic twin, DZ Dizygotic twin, Sib Sibling, OP Occlusal plane, SN SN plane, FH FH plane, MP Mandibular plane, MR Matrix rotation, TR Total rotation, IR Intramatrix rotation

*P < .05, **P < .01, ***P < .001