Table 4.

Changes in mean power frequency (MPF%) of muscles during 10 s of maximal voluntary contraction in intercuspal position depending on the temporomandibular dysfunction index Di.

		Di group
Side/gender		0			I			II			III
		n	Mean	SD	n	Mean	SD	n	Mean	SD	n	Mean	SD
Temporal muscles
Left	Females	22	−2.18	6.99	39	−6.64	5.13	25	−14.71	5.81	7	−10.44	9.14
	Males	23	−2.80	3.54	29	−6.10	5.34	23	−11.49	6.17	6	−27.83	0.82
	Total	45	−2.50	5.45	68	−6.41	5.19	48	−13.17	6.14	13	−18.47	11.11
Right	Females	22	−3.55	7.82	39	−7.39	6.11	25	−15.03	4.04	7	−11.70	3.56
	Males	23	−3.10	4.29	29	−6.66	5.64	23	−11.14	4.87	6	−25.48	1.67
	Total	45	−3.34	6.20	68	−7.08	5.88	48	−13.17	4.83	13	−18.06	7.66
Masseter muscles
Left	Females	22	−1.89	7.51	39	−12.99	7.95	25	−19.51	4.81	7	−9.79	10.23
	Males	23	−5.30	4.67	29	−10.95	4.14	23	−17.80	3.72	6	−36.77	7.43
	Total	45	−3.64	6.39	68	−12.12	6.63	48	−18.69	4.36	13	−22.24	16.47
Right	Females	22	−3.35	10.25	39	−14.85	8.80	25	−19.09	4.51	7	−14.77	4.18
	Males	23	−5.20	5.90	29	−13.31	4.77	23	−17.66	3.37	6	−34.32	7.31
	Total	45	−4.30	8.27	68	−14.19	7.35	48	−18.40	4.03	13	−23.79	11.57