Table 1.

Intergroup comparability (chi-square and t tests)

	Male		Female		Total
Damon	13		12		25
Conventional	15		12		27
Total	28		24		52
	X2 = 0.06 DF = 1 P = 0.797a
	Group 1—Damon n = 25		Group 2—conventional n = 27
	Mean	SD	Mean	SD	P
Initial age	16.04	5.20	16.77	5.32	0.623b
Final age	18.06	5.51	18.47	5.43	0.788b
T. time	2.02	0.68	1.70	0.56	0.078b
MxII.	6.60	3.68	5.13	1.66	0.065b
MdII.	6.36	2.93	5.40	1.60	0.144b

MxII. maxillary irregularity index, MdII. mandibular irregularity index

^aChi-square test

^b t test